Sherlock/WMG

"John Watson: [slowly, grudgingly.] That was amazing. Sherlock Holmes: [deadpan] You think so? John Watson: Of course it was. It was extraordinary. It was quite... extraordinary. Sherlock Holmes: That’s not what people normally say. John Watson: What do people normally say? Sherlock Holmes: "Piss off!""

- A Study in Pink

The "frustrating cliffhanger" at the end of season three will involve Sherlock and John parting ways.
Think about it. We've already seen a a huge bomb cliffhanger, and they can't kill Sherlock again. So how will they rip our heart out? Emotionally. Sherlock and John will have a huge fight, and then seem to separate forever, forcing the fans to wait a year and a half to see the detective and his blogger get back together.
 * This seems very likely given the insane amount of trust issues on both sides after the return. Not to mention Moffat saying he wants to explore stories were John gets married. The whole series could revolve around John being married, living away from 221b and the boys struggling to still be friends and solve crimes together while John is trying to balance it out with his new family and Sherlock is jealous of "Mary" for taking John away. Then, on the final episode, when things finally seem to be sorting themselves out and the three have found how to get on with each other, Mary will be injured or killed in a way that leads John to blame Sherlock.

Anonymous is
While the style seems like it would fit Moriarty more, there is one exchange in the comment section of John's entry for The Great Game that makes no sense with that theory. After Anonymous comments "I do like a good story", SH responds with "Still alive then?", to which Anonymous says "Oh, very much so. See you soon." Consider what happens earlier in the episode, and afterwards:  It's likely Sherlock didn't know the identity of Anonymous, save that it was someone who was watching him, but not Moriarty, which would have allowed him to link that person to the one who made the call at the Pool. The exchange was a promise to meet in person in the near future, and they do.
 * The still alive comment could be a reference to Moriarty's ringtone, "Staying Alive".
 * It seems like the precisely the kind of pop culture Sherlock would delight in ignoring, though.
 * This makes sense as the puzzles Anonymous left on Sherlock's blog, while still fun, are certainly not of Moriarty calibre. Not to anyone who has Google as their homepage. On the other hand, this could be Moriarty patronising Sherlock with "child's play" games.

In The Hounds of Baskerville, Sherlock was coming off cocaine, not cigarettes.
It's never directly referred to, of course- it would drive the ratings up. They at first never call what Sherlock is after anything at all. Sherlock says "I need some, get me some" and John responds with "nobody within a two mile radius will sell you any." But he and John both know exactly what they're talking about. Sherlock hasn't paid off cigarette merchants, he's paid off all his dealers. It would be easy for him to take a taxi ride to get some more cigarettes outside that two mile radius, but much harder for him to locate a dealer outside of his usual ones. It's only after Mrs Hudson comes in that Sherlock claims to be looking for his cigarettes. After all, Sherlock uses patches, so even if he had no cigarettes, it wouldn't be any need to go "cold turkey" like that. He wants cigarettes because he needs something to take the edge off the coke cravings. It explains why John, who's keeping an eye on the whole thing as a friend and as a medical professional, gets fairly upset at the idea of going to Dartmoor without Sherlock. Later, John seems to think that Sherlock being "pretty wired" would be enough to make him start seeing things at Dewer's Hollow. Coming off cigarettes wouldn't make you that wired.

Alternatively:

Sherlock's "Nicotine patches" are laced with cocaine.
Because that would be a staggeringly brilliant way of Sherlock hiding his drug stash from the depredations of John, Mrs Hudson and Lestrade's fake-out drug busts. It's in character for Sherlock to "hide" something like that in plain sight using something nobody would look twice at during a drug raid. It would also explain how he appears to be getting high off the patches- even three nicotine patches wouldn't give you an instant buzz.

How Sherlock
After the events of The Reichenbach Fall, John is so distraught that he needs to get away from his former life and the people who know about Sherlock, so he moves out into the country and starts going by a different name: Arthur Dent. He slowly builds a new life for himself, including a new best friend named Ford. Then one day, Ford reveals that he is an alien, and he and Arthur set off into space to escape the destruction of the earth. Meanwhile, just before Arthur and Ford join him on the Heart of Gold, Zaphod Beeblebrox pushes the button on the Infinite Improbability Drive, and something infinitely improbable happens: in the past, Sherlock Holmes misses the ground and flies away (since, obviously, the way to fly is to throw yourself at the ground and miss), and, even more improbably,  (hey, that's less improbable than everyone turning knitted). Sherlock flies around for a bit, then lands and begins watching John silently, knowing that he has no explanation he could give him for his infinitely improbable survival, until the party where Arthur first meets Trillian. When Sherlock, who has been following John/Arthur like a stalker, hears Zaphod tell Trillian that he has a spaceship, he gets curious and follows them. Zaphod and Sherlock bond over their shared egotism and become friends, and the three of them leave the planet together shortly before Arthur and Ford do. When Arthur and Ford join Trillian and Zaphod and Sherlock on the Heart of Gold, John/Arthur and Sherlock are reunited at last, though their touching and emotional reunion is somewhat deflated when Zaphod starts catcalling and tells them to get a room.

In The Reichenbach Fall, Claudette wasn't reacting to Sherlock.
It was John. Moriarty and Sherlock don't really look alike at all, so it's difficult to see how she could mistake the two... but we've yet to see Sebastian Moran, or the man who actually did the deed and kidnapped Claudette and her brother from their school. When Claudette starts screaming she is looking up, but John is standing directly behind Sherlock and all she's doing it pointing vaguely in their direction. Who's to say Sherlock's the one she's screaming at?

The hidden camera was Sherlock's, not Jim's.
On the day Jim was acquitted, Sherlock realised he needed to record the meeting at the flat and anything else that went down, and put the camera on the bookshelf. Jim can't have done it. He would have had to scale the bookshelf in front of Sherlock to put the camera where Sherlock later "found" it. Sherlock's "realisation" later that there was a hidden camera was a complete act. He already knew that much of what later happened was going to be circumstancially against him unless he had some way of recording what was really happening- in Baker Street, anyway. The book was moved back when Lestrade and Donovan are there about the kidnapping case; Sherlock has since moved the book over the camera when he "finds" it later, probably so that there's no chance that John will accidentally see it.
 * The kicker: Who was the camera for the benefit of? Initially, Mycroft. It was far too dangerous for Sherlock to even text Mycroft, as it might have been intercepted. This was a way for Mycroft to know what was going on without putting Sherlock in danger.

In The Reichenbach Fall, Moriarty
Basically, in order for Moriarty to have a convincing enough story as an actor, he had to have at least some proof that could be twisted. So, he kills two birds with one stone and while building up a successful CV as a children's TV presenter, also conditions children to be frightened of something about Sherlock. I like to think it's his coat, because Moriarty appreciates good tailoring. An expensive Dolce and Gobbana [I think? I don't especially look these things up] coat would be rare enough to not get an accidental reaction out of the children, then Moriarty goes back and, wearing a coat of the same brand, cementing the children's subconscious fear of villains in such attire, violently kidnaps them. Or hires somebody else to do it.

In The Reichenbach Fall, Mrs Hudson
As a result, John had a massive nervous breakdown, and everything that happened from the time he returned to 221B after and spoke with her, is a figment of his imagination, or at least very, very questionable in whether it happened the way John thought it did. It's why he can't go back to Baker Street, not because but because

Alternatively:

In The Reichenbach Fall, Sherlock really was
Because that would be an awesome mindscrew for the audience.

In The Reichenbach Fall, Sherlock actually
In the first episode of the third season, we will see John turn around at the, walk towards Sherlock, and then walk through him. That's why they had that scene at the very end, to make us feel confident that, then mess with our heads during third season.


 * Alternatively, this theory will be something they really do, and it will turn out

By the time of the last scene in The Reichenbach Fall, John
His but listen to what he says. We're mostly too busy having our hearts broken to really pay attention to how weird what he says is. it's still a massively out of character, impractical thing for him to say. Something John saw or heard while Sherlock was on the roof (or perhaps before) put the seed of doubt in his mind: he knows things don't add up somehow. Perhaps, as someone mentioned below, because Sherlock's tiff with Mycroft makes little to no sense and Sherlock never mentioned him at all; perhaps because if Sherlock had "researched him" he'd have known Harry was his sister, not his brother. Either way, John certainly isn't stupid and even at that point he's starting to piece things together.

Sherlock rerouted the connection from the hidden camera to the laptop.
Otherwise, there's little to no payoff for the hidden camera. After they find it, Sherlock is seen fiddling with it, and typing something into the laptop (which is, from memory, John's.) We never see or have it explained what he's doing, and the hidden camera is never mentioned again, so it's odd. He's having a tense conversation/argument with John at the time, where he unfairly accuses John of doubting him, which may just have been a distraction so that John doesn't ask what he's doing at the computer. On the roof later, Sherlock asks a lot of leading questions and confirms a lot, getting Jim to explain his evil plan in quite a lot of detail. Why? Sherlock doesn't like people explaining. He likes to "get it" himself, it makes him feel and seem smarter. He was teasing out Jim's confession. He had the camera (which had sound, as earlier demonstrated when it picked up Lestrade's voice) on his person somewhere. At some point, somebody (probably John) is going to find a recording of most if not all of Jim's confession on the laptop. Possibly, also on the phone that Sherlock is so anxious to very, very carefully throw away gently.
 * If he had the camera on the roof, it wouldn't have just picked up Jim's confession. It may well have picked up his
 * That camera was there at 221B the night the children were kidnapped. If it records time and date, and provided Sherlock was home that night, it may prove to be a pretty solid alibi for Sherlock, assuming anyone still seriously thinks he kidnapped the children (a theory which falls apart if you look at it for longer than five minutes.)
 * It's also possible that Sherlock was rigging the camera to play a previously recorded fake feed of comings and goings in Baker Street, causing Jim to think the camera was still in place when Sherlock had removed it. He texts Jim "Got something of yours you might want back." Jim never asks him what it is. It can't be the code, as that's not something Sherlock had access to and even if he did, you can't pass a thought back and forth between two people like that. It's an object Sherlock's talking about, and the only other object of Jim's he still has is his little knife.
 * The camera not only picked up Jim's confession, Sherlock shifted it at the last minute to a position where it picked up
 * Anything the camera did pick up will be found by John, who will put the footage/recording on his blog- which is already popular- and the whole thing will go viral.

Sherlock's Out of Character moment comes much earlier in the episode than anyone thinks.
Moffat said in an interview, “I’ve been online and looked at all the theories, and there’s one clue that everyone’s missed. It’s something that Sherlock did that was very out of character, but which nobody has picked up on.” This OOC moment came about halfway through Reichenbach, much earlier than the roof scene:

Season 3 will involve Sebastian Moran buddying up with John.
As part of watching him to see if Sherlock is really dead. Possibly also for reasons of curiosity - John wondered already about Moriarty's "John Watson", it's possible the curiosity goes both ways. It's also a sensible way to introduce a new and engaging antagonist while keeping John in the picture.

Moriarty is the devil.
Pretty self-explanatory. He had no problem shooting himself at the end of Reichenbach because he was simply using Jim's body as a shell.

Sherlock never arranged the phone call to John about Mrs Hudson.
... Moriarty did. Possibly, it was he who actually made the call itself- he's a talented actor. Why Moriarty and not Sherlock? Because Moriarty was boredly waiting for Sherlock, and he knew Sherlock wouldn't or couldn't come out to play with him while John was around. Sherlock deduced that the call was a diversion intended to get John out of the way, hence why he refused to buy into it or react emotionally- and he let John believe it was true.
 * This seems likely. The episode actually follows the plot of the original story, The Final Problem, pretty closely, from Sherlock's fall from grace, to escaping with only John in tow, to deciding that . In the original, a Swiss messenger brought a message to Watson that an English woman was dying, and when she was so far away from home she desperately wanted the company of an English doctor. Holmes knows it's a decoy to separate him from Watson, but goes along with it to spare his friend the trauma of seeing him . Of course, in this version, John snookers that plan by refusing to stay away when he discovers the trick.

There are five red herrings to do with Sherlock's death
And they all start with B: the Building, the Bike, the Ball, the Binary and the Body.

Because it all seems too obvious for the fandom to have worked out (mostly) already, and the trolling duo that are Steven Moffat and Mark Gatiss probably set it up this way so they can giggle at the incredibly wrong fandom being diverted in entirely the wrong direction for the next year or so.

Sherlock knew the whole time about Mycroft's mistake, and Mycroft helped him fake his death
It's extremely far-fetched that, even given their icy relationship, Mycroft wouldn't tell Sherlock that he'd given information to Moriarty and as such had freakin' assassins on his trail. He's protective of Sherlock. He wouldn't just let John know and hope John would a) tell Sherlock, and b) be able to protect him. There was some sort of agreement between Mycroft and Sherlock which meant that they had to avoid contact (so Mycroft would fall under Moriarty's radar and not be made a target if and when shit started getting real). Mycroft's initial meeting with John was deliberately to give John the impression that the two weren't on speaking terms just then. John is astonished that Mycroft apparently wasn't going to tell Sherlock about the assassins; Mycroft explains something extremely vague about "old scores", which John doesn't entirely buy. After all, they seem on okay terms after The Hounds of Baskerville. There's nary a text between them in this episode and that's very suspicious. As for Mycroft's role in his brother's "death", while Molly can no doubt do creative things with bodies and autopsy reports and such, Mycroft could relocate Sherlock and create him an entirely new identity. Among other things.
 * This would also be in keeping with the original stories, in which it's revealed in "The Empty House" that Holmes only informs Mycroft that he's faking his death so that Mycroft can manage his affairs in London until he's ready to resume his normal life.
 * I have to wonder about why Mycroft seemingly told Moriarty all about Sherlock and then let him go. Did Moriarty escape somehow or is it a part of Mycroft's and Sherlock's elaborate plan to bring down Moriarty's network of spies and criminals?

John is a Reality Warper
Sherlock did die after he fell, but John begging him to come back by his grave warped reality.

How Sherlock survived his suicide and faked his own death.
The episode title is "The Reichenbach Fall" instead of the "Final Solution", why? Because Reichenbach translates to Richard Brooke. Richard Brooke is the one who fell of the roof, not Sherlock. Moriarty had some kind of face mask to make himself look like Sherlock, that is why the kidnapped little girl was afraid of Sherlock when she saw him and that is how Moriarty's body ended up looking like Sherlock.


 * Sherlock was being watched while on the rooftop, with his friends' lives hanging in the balance. There's no way he could have done anything odd up there without endangering them. Plus, the camera work has been very careful to show us that it is Sherlock, alive, who talks to John on the phone and jumps down afterward. Rather than a Gore Discretion Shot, the camera is kept on his falling body the entire time. No, more likely that he took his chances and did what he could to improve them - it's not that high a fall. With the right trajectory (he falls very gently into it, and you'll notice he keeps his arms and legs spread out during the fall to slow himself down as much as possible) and the body kept loose and relaxed (which can also be achieved with a drug), serious damage can be avoided. Plus, it would kind of undermine the whole badassery and heartwrenching-ness of his farewell to John. No, far more poignant for him to have taken a significant risk. Also, he was playing with a rubber ball beforehand. Pressing a rubber ball into your armpit cuts off your pulse in that arm. Ergo, the Law of Conservation of Detail states that it was him down there on the pavement.
 * Plus, it was Sherlock who chose the meeting place.
 * And in terms of the need to furnish a body for official purposes and assuming a closed casket or cremation...Molly's father died recently, didn't he? And didn't he remind her a bit of Sherlock?
 * My Dad had an idea; what if Sherlock was so insistent that John stay where he was not just because of the sniper, but because he'd managed to set the biker up? That way, John would be too disoriented - if he wasn't already - to notice something off. But beyond that, I'm not entirely sure.
 * Another very likely theory is that Sherlock fell into the laundry truck.
 * He fell in the truck, which was manned by accomplices that dumped a bashed up body Molly had doctored to look like Sherlock on the curb. Truck drives away, unnoticed in the excitement.

Sherlock will crash John's wedding in the first episode of Series 3.
This will be how he comes back. When the priest asks if anyone has any objections, Sherlock will burst in and grab John because they need to go off and solve a crime. (Catch Sebastian Moran?) Sherlock's been ruining John's relationships all this time, might as well go all the way
 * Are you me? Because I was seriously planning to add this before I saw that someone had beat me to it.

In Season 3, Sherlock is going to recreate himself as Richard Brook.
Well Moriarty kind of did suggest it, practically, with And Sherlock did happen to give Jim a cup of tea at 221B, thereby conveniently obtaining his full DNA and fingerprints. As Irene points out in Belgravia, DNA is only as good as the records you keep. And if you know the record-keeper... and she happens to be awesome...

Sherlock will become a serial killer in Season 3.
He'll be bringing down Moriarty's network. Probably hunting them down and killing them before squeezing them for information. We already knew as early as A Study in Pink how ruthless he can be with his enemies. To the police, it would likely look like a new serial killer is on the loose. A further reason is Dramatic Irony - in bringing down Moriarty & Co., he'll become more like them. Throughout the series, "What if Sherlock Holmes started killing people?" has consistently been posed as an issue, culminating in the blunt "I may be on the side of the angels, but don't think for one second that I am one of them." Even more compellingly, there's the matter of characterisation. By the end of Reichenbach, Sherlock has finally become A Good Man - so logically, the only way to head after that is down. In short: We've explored his good side, now it's time to explore his dark side.


 * I think this is close to a really good guess - particularly if you take the plot of Doyle's the Adventure of the Empty House into account. My spin on this is - Sherlock is allowing the news to get out he is a fraud and is faking his death so he can usurp Jim Moriarty's position (after all he will be accredited for being the man behind Moriarty's criminal consulting). He will use it to root out the assasins network Moriarty has built up. In fact Shelock needs to because so long as even one of Moriarty's henchmen is alive and free, Watson, Lestrade and Mrs Hudson (and maybe the rest of his friends) will never be safe.

theimprobableone is SHERLOCK.
Either because he's using a sockpuppet to tell people what he REALLY thinks, or because he's a lot more mentally ill than anyone else ever suspected and genuinely has a second personality.

Sherlock's mother rejected him when he was a young child.
In the commentary to "The Great Game", Benedict Cumberbatch and Mark Gatiss are talking about the scene where Mycroft visits Baker Street and introduces the missing Bruce-Partington plans. They explain that there was much more dialogue in this scene filmed, most of it was cut, but Gatiss says something about using it later on, something about how a young Sherlock Holmes had disturbed the peace in his home. Cumberbatch begins to say "Sherlock finds out his father is having-" before cutting himself off.

In Belgravia, there's an exchange at Buckingham Palace and an implication at a morgue to suggest that Mycroft, who is significantly older than Sherlock, basically raised Sherlock himself.

In A Study in Pink, Mycroft suggests that Sherlock's attitude "upset Mummy", and tells John that Sherlock is "resentful."

Putting it all together, we might assume a scenario where a very young Sherlock, having his skills of deduction, deduced that his father was having an affair. Being- well- Sherlock, and young, he may have let this be known in a blunt and unsympathetic way (e.g., casually one morning at breakfast.) Exit Dad, Mummy takes it out on Sherlock. (Sherlock's line "it wasn't ME who upset her, Mycroft" seems at first glance to be an accusation that Mycroft upset Mummy; but what he could mean is "I didn't upset Mummy by telling her Dad was having an affair, he upset her BY HAVING ONE.") Anyhow. If Mrs Holmes withdrew from Sherlock either to "punish" him for "ruining her marriage", or in revulsion of his uncanny skills, it's possible that Mycroft then had to step up for his little brother and basically raise him himself. Sherlock may have learned his uncaring nature from Mycroft, and both boys may have used it as a self-defence mechanism. Mycroft's bond with his brother is a protective one, and he understands what it's like to be able to see far too much about people around him but not have much personal experience with human emotions like love. But unlike Sherlock, Mycroft understands the basics of tact and courtesy (mostly) and is able to put his skills to use to advance his career. Sherlock may resent Mycroft's well-meant meddling because he didn't want Mycroft to "be mother", he wanted his mother to be mother. Taking that out on Mycroft, when Mycroft apparently did the best he could, isn't exactly saintly of Sherlock but it adds a new complexity to his character.

And then, of course, there's his relationship with Mrs Hudson. She worries about him; she does his laundry (say so in John's blog), buys his food and cooks for him, tolerates his eccentric living habits and accepts how weird the inside of his head is... and as A Scandal in Belgravia shows, she is a bit of a kindred spirit, conspiring with him, showing herself willing to do anything to protect him no matter what the cost. She is the mother Sherlock never actually had growing up. Puts extra weight to Sherlock barking at Mycroft for insulting the woman he sees as his mother, and warmth to "but do, in fact, shut up." Sherlock feels justified in saying things like that, because he's familiar with her and genuinely does love her, whereas Mycroft saying the same thing is basically just a lack of respect.

Mycroft is paying Mrs Hudson to spy on Sherlock for him.
Would explain how he knew so quickly that John had "moved in with him [Sherlock]", even though he actually hadn't yet. It's not implausible that when Sherlock and John left to go to the crime scene in Brixton, Mrs Hudson called Mycroft to let him know that Sherlock had been called to a case and that John was with him, giving Mycroft time (though little of it) to gather as much info on John as possible prior to kidnapping him on the way home. The only other person who seemed to know about John moving in to Baker Street is Mike Stamford, who doesn't seem particularly close to Sherlock and would probably not be much use as a spy. This would also explain how Mrs Hudson can afford to have Sherlock and John live at 221B at a discount.


 * Interesting that you mention that Sherlock says he gets the flat at a discount. In the original books, John says that he noticed once how much Sherlock was actually paying for his share, and it was a rather large amount. With this reasoning, it may be that on the final bill, Sherlock pays the "discussed discounted amount", and doesn't realize that Mycroft is really paying Mrs.Hudson the difference. That obscene pay to spy on Sherlock might also be why Mrs. Hudson deals with the constant property damage; because She has to spy on Sherlock to get money and she knows that Mycroft will pay for the property damage even if the boys don't.

Sherlock has a "romantic" history with Sgt Sally Donovan.
By "romantic", I assume that he has done to Sally what he later does to Molly- blatantly charmed her to get information or some other thing he wanted to solve a case, then blanked her. He introduces her to John in 'A Study in Pink' as "an old friend" significantly. In the later scene at Baker Street, Donovan starts passionately telling Lestrade "he's just a lunatic, and he'll always let you down!" and her tone is quite strange- she sounds like she's going to burst into tears, and since there's absolutely no evidence that Sherlock has ever ultimately let Lestrade down, we can only assume she's personalising the issue because Sherlock has a history of letting her down.

Sherlock will appear to die at the end of Reichenbach
If we're sticking to the original story of Reichenbach, Sherlock falls of a cliff with Moriarty and die. (He gets better.) It seems very plausible, especially since it's set as the last episode of the season-what better cliffhanger would be the hero appearing to die?
 * And hey, if they don't commission a third season, Sherlock can just stay dead, ending the series with a bang instead of a whimper.
 * Which ironically was how Arthur Conan Doyle originally intended the books to end. If the BBC starts filming a third season, we'll all have conclusive proof that history does indeed repeat itself.
 * If they make us wait three years to Empty House us, I'm going to die. Except if they manage to bring a new series out of nowhere, with no warning beforehand, in which case I will be amazed and delighted with their ingenuity.
 * In the book, Sherlock Holmes' death wasn't meant to be a trick, it was meant to be real. Doyle had a difficult time explaining how the hell Holmes got out of that one when he resurrected him three years later, and it's not terribly convincing even by the standard of Doyle's outlandish plots. There's no way a ploy like that would in any way work in a modern context, BUT- if you read "The Adventure of the Empty House", you'll see that there was one soul and one alone who knew Holmes was alive- Mycroft. Sherlock needed him to keep an eye on him and send him funds. The whole "chasm" conceit could end on a much more realistic note- Sherlock being declared dead at a hospital, after an apparent serious injury, and John and everyone else told that he was dead. Mycroft has shown himself to be so Crazy Awesome that it doesn't seem remotely beyond his powers and abilities to have a death certificate faked for his little brother. God knows he might even be crazy enough to mysteriously produce a horribly mangled body to bury. We'll see soon, however.
 * He organized a plane full of corpses; one tall Caucasian male shouldn't be hard

Jim actually isn't Professor James Moriarty. He's James Winter.
Consider the following:

Many of the characters in the credits are given by their full names, even if it isn't necessary. Dr John Watson? Really? The audience needs the title as well as the first and last name? But when it comes to the man threatening them, it's simply Jim. Not Jim Moriarty, not Professor Moriarty, just Jim.

Second, the story in which Doyle tells us Sherlock has turned down a knighthood? "The Adventure of the Three Garridebs." The fact that Sherlock jokes about it in passing in this episode is quite interesting.

Third, if "Jim" could stand for James when we think he's Moriarty, why couldn't it stand for James in the name James Winter?

Fourth, to those Sherlockians out there, you know that "The Adventure of the Three Garridebs" is near to most of the fandom's hearts. It's one of the very few times Sherlock ever reveals that he cares for Watson or values their friendship at all. In the end of "The Great Game," we have an extremely similar situation, which is different than the note that Holmes wrote for Watson in "The Final Problem," in that Watson actually *sees* Holmes emotional over him.

Fifth, "Jim" leaves for a bit, and then comes back after the tension seems to be cleared. Could be that he changed his mind. Or he could have been receiving instructions based on the real Moriarty's analysis of the confrontation. He may have initially intended for Sherlock to be played with for a bit longer, but decided he was too dangerous, and so told his subordinate to go back in and take him out.
 * Actually, I think he really was Richard Brook, the actor, because all of his information as an actor was real. As Sherlock himself says, it is easiest to believe a lie with some truth mix in with it. And the truths there in was not just about Sherlock, but the actor Richard brook (AKA Jim Moriarty). The red herring that is Richard Brook posing as Moriarty will make it easier for the REAL Moriarty to continue his operations from underground operations centers.

Moffat and Gatiss gave us that ending as a get-out clause in case the series flopped.
Just like Jekyll, which Moffat also wrote.

If Sherlock had failed, they could make one more miniseries revealing Jim to be Moriarty and then have some kind of resolution to tie up all the loose ends.

If however, the series was a hit (which it was) then they can go on to set up a longer, better, more complicated arc where Jim turns out to be a decoy etc., etc.

There's a whole bunch of Chekhov's Guns that the writers have set up to make things interesting if they need to, but which they could disregard if they just needed to end the whole thing.

Sherlock takes place in the same universe as Jekyll.
It would be so awesome if there was a Steven Moffat fictionverse.
 * Here's a YouTube interview where Moffat is speculating briefly on what a meeting between this version of Sherlock and The Doctor would be like. We can but dream:
 * Link to this video/article, please?
 * There is a (fanmade) trailer for this

The sniper at the end of The Blind Banker was Colonel Sebastian Moran from The Empty House
Gee, a sharpshooter in Moriarty's employ. Who could it possibly be?
 * Perhaps he was the Sebastian from earlier.
 * Given the number of nods to the original books (including some fairly obscure bits), I'd be very surprised if Sherlock's school acquaintance being called "Sebastian" wasn't intentional. Could still be a red herring, though.

The Princess Bride (or at least the scene with the poisoned drinks) never existed in this universe.
It's clear that the original Sherlock Holmes stories don't exist in this universe. The ripple effects must have wiped out all sorts of derivative works. It's possible that one of them was that scene.

This would explain why nobody even mentions the possibility that both choices are poisoned.

Moriarty planned the whole thing and is the only one who knew that both drinks were poisoned.
He is Moriarty, and that's kind of his thing. He inoculates the cabbie without telling him because this guarantees him victims - victims he's paying to get, via sponsorship—and allows the cabbie to think that his 'successful' choice is due to his own brilliance or - as he said - because God likes him.

Either way, the cabbie is probably not particular about how his 'game' works, since his death is certain be it by aneurysm or pill. He's happy to keep playing the game because of the money going to his kids.
 * The idea that Moriarty planned this gets even more plausible if one takes note of the number of pills in the bottles. When the cabbie first starts going on his murder spree there are quite a few, but by the time he gets to Sherlock there's only one left. From the beginning, the plan must have been for the cabbie to kill four people, then swing 'round to 221b Baker Street and pick up Sherlock (the fact that Sherlock figured it out at that exact moment is merely a happy coincidence). The whole thing is just a way for Moriarty to introduce himself to Sherlock.

The Princess Bride exists, but Sherlock has neither read nor seen it
In the original Sherlock Holmes stories, Watson once remarked that a significant hole in Holmes' knowledge base included popular fiction of the day. Holmes tended to refuse to learn info that didn't seem relevant to him, and few things seem less relevant to the fact-minded person than popular fiction.

Today, 'popular fiction of the day' would include The Princess Bride. Sherlock doesn't consider this solution as a possibility because he hasn't read or seen the source that codified this solution to the real problem.


 * I really like this idea, though I do have one question (sorry), I know this book/movie is part of American pop-culture, but how popular is the movie/book in Europe? Specific England? If it is as popular there as in America, then it can be assumed that in Sherlock this book/movie either doesn't exist, or isn't something that Sherlock has read. Does anyone know the populatity of this book/movie in England?
 * It's a pretty popular movie here in England. Not everyone knows it, sure, but it has cult status probably equal to Labyrinth.
 * Thank you~ Alright, then I agree that Sherlock just hasn't ever read it because it's not important to him. XD
 * And I'm afraid you are misremembering: the quote from ASIS is: 'knowledge of sensational literature: immense'

This Sherlock Holmes is a grown-up Encyclopedia Brown using a pseudonym and a fake accent
That's why he was in Florida to help out Mrs. Hudson.

Sherlock, Mycroft, Moriarty & The Taxi Driver are Sparks
A few geniuses in a world full of norms? Ring any bells?
 * Yes.

Sherlock is the 12th Doctor
This should be the the most popular and obvious WMG about this show. The entire series most likely takes place after Matt Smiths regeneration and the return of the Time Lords to our reality. Since the Doctor doesn't have to singlehandedly save the universe any more he decides to go into full retirement on earth. But after a while he gets bored and decides to become a consulting detective for the British police and secret service under the pseudonym of Sherlock Holmes.

And if one looks at the clues it's all there from Sherlock's eccentric outfit, the way he sees the forest and the trees of a mystery, the way at times he seems to channel small bits of the persona of the Tenth Doctor during his thought process, the reason Sherlock seems "bored" with nearly everything in ordinary life and the final nail is after a while of being on his own for a while more he still needs a assistant/companion thus we have Dr. Watson.

Also Sherlock's brother Mycroft might actually be the Doctor's ACTUAL brother sent to check on him by their mother, the now lord president of Gallifrey who has his own companion (the hot chick that was constantly texting.)

Sherlock is The Doctor with Amnesia
Think about it. He craves an assistant, is extremely clever in a slightly alien way, and doesn't mind a bit of running.

In this 'verse, Sir Arthur Conan Doyle has been swallowed up by the cracks in time, and the original Sherlock Holmes stories were never written. The Doctor, after a traumatic event, develops amnesia but seizes upon a character from his memory and assumes his identity. UNIT hears about this and sends an agent to assume the identity of Mycroft to keep an eye on him. The Master has been resurrected for the umpteenth time and gleefully takes on the persona of Moriarty to play with The Doctor. Dr Watson turning up is a happy coincidence.
 * The Doctor is similar to Sherlock. The inspiration is....elementary.
 * Benedict Cumberbatch and Matt Smith have the exact same face.
 * Umm, what?
 * Steven Moffat went on record saying that he considers them to be polar opposites. The Doctor is like an angel who wishes to be human; Holmes is a human that aspires to be a god.
 * So Sherlock is the Scotland Yard Valeyard?
 * I had him pegged as the Master.
 * And so...

Sherlock is The Master.
It's more likely that Sherlock is a Chameleon-Arched Master as whenever the Chameleon Arch is shown in Doctor Who, the resulting human keeps some of their traits from being a Time Lord - Professor Yana was an engineering genius who still heard the drums, and Professor Smith hated guns, liked kids and was nice (ish) to Martha despite her being black in an earlier time. Sherlock cares about nothing but knowledge and proving himself to be the best. He also quite happily fires guns several times. He hates being around people - except John, apparently - and gets his kicks from violent crime and murder. Ergo, not the Doctor. The Master.
 * Sherlock's similarity to the Doctor has already been noted, but can you imagine the Doctor cold-heartedly torturing a man? Scornfully referring to human minds as 'funny little brains?' Casually describing himself as a sociopath? Didn't think so. But the Master is also a good bit like the Doctor . ..
 * The Doctor has called humans "stupid apes". It all depends on his regeneration. Some are nicer than others...
 * The Doctor describing human minds as 'funny little brains'? Absolutely. He says that almost word for word in The Empty Child.
 * In, I believe, "Masque of Mandragora," the Doctor says to Sarah Jane that "You humans have such tiny little minds. I don't know why I like you." Granted, Sarah turns this into a Crowning Moment of Heartwarming by replying "Because you have such good taste!" but the Doctor isn't always, 100% pro-humanity.
 * Benedict Cumberbatch is apparently going to play the Master. Make of that what you will.

"theimprobableone" is Arsène Lupin
One, presumably Mycroft has better things to do with his time than post on Sherlock and John's websites and figure out the hidden messages. Two, "theimprobableone" seems a bit more of a fan who's never met Sherlock than his brother, and his posts seem to convey a bit more energy than Mycroft would post with. Also, as a government employee, Mycroft would use capitals. Now as for why it's Arsène, Arsène is a thief specializing in seemingly impossible crimes, until the facts are revealed and it turns out that they are merely improbable. It is also far past time that Arsène appear on Sherlock's turf as opposed to the other way around, and it's not like he's got a copyright hanging around his neck anymore either. He also makes comments such as saying John seems stupid and how he can match Sherlock's intellect, which would match John's portrayal in the Arsène Lupin books as really, really stupid (Maurice Leblanc did not seem to like him very much, taking every chance he got to get John out of the picture). But all this is small fry when compared to the fact that It Would Just Plain Be Awesome.
 * Please let this be true. A modernized version of Lupin would be epic in numerous ways... mostly all the new disguises he would not have had access to in the original setting. The fact that Holmes (or a Captain Ersatz depending on the publisher) was used as Lupin's Worthy Opponent makes this all the more interesting.
 * More evidence for this theory is a picture of what is possibly the Eiffel tower on Dr. John Watson's blog. Look at the one in the middle of the top row. Is it just me who thinks so?

"theimprobableone" is Irene.
Because I think that would be cool, and the chance of anyone being able to outsmart Sherlock Holmes in future would be considered pretty improbable.
 * I'll do you one better: on Sherlock's website, while Sherlock is muttering about Bond films, "theimprobableone" posts a comment about how "Citizen Kane" is better. Why is this important? Because there are parallels. In "Citizen Kane," Kane is discovered to have had an affair. The affair ends his political career, sort of like how the political figure in "Scandal in Bohemia" would have had a hard time if anyone discovered his previous involvement with Irene. Furthermore, Kane marries his mistress and then forces her into an operatic career. Irene was an opera singer. Coincidence? I think NOT.
 * "theimprobableone" also talks a lot about how Sherlock should find someone who can "match his intellect." Irene is famously one of few people who did.
 * theimprobableone also wonders how John could have missed the case (in s01e02) would be pink. This could be snarky, like John's comment "Why didn't I think of that?" in the actual episode, or it could be Irene's savviness about female outfits. You can easily imagine her picking detail that up right away.

"theimprobableone" is Anthea.
Because she must be doing something on that Blackberry.

Sherlock is a Technopath
Sherlock's using the mobile phone to send texts to everyone at the press conference, and that time he recalled that long list of directions in the scene which showed the maps, and other times like them: it's not just that he's a technical genius with a photographic memory. He is a technopath like Micah from Heroes.

He was not remembering all of that information. He was accessing it with his mind.


 * Or he's like Gary from Alphas, and can read electromagnetic wavelengths. See the news, access GPS, read people's texts...

There is more than one Moriarty.
How can someone be "more than a man"? If he's two, three, or ten men who all use the same name! Think Ra's Al Ghul in Batman Begins.
 * Maybe Moriarty is more than meets the eye?
 * If I remember correctly, didn't book!Moriarty have a brother called James?
 * Nope—that was Moriarty's first name. Which should have tipped us all off from the beginning, really.
 * Actually, it was both his brother's name and his own name. Continuity was not Doyle's strong suit.

The cipher from "The Blind Banker" is the Yellow Sign.
It's yellow, and people die after they see it.

Sherlock has a bit of a crush on John
Okay, so this is no place for Shipping. However, it's a genuine wild guess.

As a sociopath, Sherlock would need to feel, at minimum, that John was the best of a bad lot to put up with living with him. Sherlock seems to accept that people assume they’re a couple. He doesn’t turn John in when he. He manipulates John so that  (He doesn’t mind working alone.) He seems eager to get John out of his clothes.

The reason he told John he was married to his work, and therefore not interested? Sociopaths can't deal with emotions.

Not exactly conclusive, but this is Wild Mass Guessing.

This becomes even more believable when you consider how  this is interesting because, earlier in the episode, he says that he doesn't care about the people whose lives are at stake as long as he can get the job done and save them. It makes you wonder what sort of feelings he would have to have for someone to make them an exception and evoke an emotional reaction like that.

This is also slightly evident in the scene when John and Sherlock are looking at the flat for the first time. The moment John comments that the place is a mess, Sherlock stumbles a bit and then moves a few things around in a useless attempt to clean up. Sherlock is normally cold and doesn't change to suit another person, except here. If you think about it, the obvious reason for such a behavior would be to better suit his living conditions for John. In order to please him on some level. Of course this all bollocks if Steven Moffat is just messing with us. Again.

Subset of above, said crush isn't sexual
Sherlock being asexual is a pretty solid fan theory, but that doesn't mean that he's incapable of romantic feelings. Overall it seems like Sherlock is a lot more concerned with John than he is with anyone else, he goes to any lenghs to keep him safe, tries to apologize when he's angry and considers him his only friend. There are also a few moments of what might be interpreted as tenderness or at least admiration from his side, such as.

One might think that he keeps talking about John as a friend partly because he's never had one and partly because of his asexuality. Sherlock isn't really one to question norms as he relies on solid predictable patterns to make sense of the world, and he's mostly detached from other people which means that he's never explored his relationships to or feelings for other people. The only thing he knows about love or romance is what people tell him, and the dominant story is that love always includes sex. When Sherlock then does develop strong enough feelings for someone, he's going to categorize them as a friend because he has no point of reference and because being as antisocial as he is, he has no interest in looking for definitions outside the norm.

John is bi, and at least a little into Sherlock
As long as we're talking about the above possibility, we may as well examine the other side of the coin. John Watson obviously likes women; he hits on Sarah and Anthea within moments of meeting them. But then, he's similarly efficient in interrogating Sherlock on his relationship status and sexual orientation immediately after meeting him. In the scene in the restauraunt, after Sherlock says he doesn't have a boyfriend, John smiles, licks his lips, and mentions that he's single. Shelock Holmes then concludes John is interested in him; Cumberbatch even does that little thing he does where his eyes move rapidly back and forth, making it clear he's using his Sherlockian powers to reach this conclusion.

Also relevant: despite constantly having to clarify to everyone that he and Sherlock are not couple, John never actually denies anything except actually being in a relationship with Sherlock. A series with this many Mistaken for Gay jokes, and not even one "I'm not gay"? Suspicious.
 * For the record, John does indeed say "I'm not gay" in the comments on one of his blogs, but supposes Sherlock might be ; of course, he could still be bisexual, or otherwise.
 * On the blog, John only says he's not gay when he's directly prompted to say if he's gay or not; initally, he ignores the question. So the argument more-or-less still holds: as a character, John seems to lack any interest in clarifying that he isn't gay, despite the fact that pretty much everyone thinks he is. Of course, this could just be because it's not a big deal to him, but it'd be still kind of unusual for a straight guy with John's generally high degree of interest in getting laid. Regardless, from an out of universe perspective it seems impossible that the ambiguity is accidental given how much talk of sexual orientation has occurred on this show already. Either Moffat and Gatiss are strongly committed to leaving it open ended, or they're setting up one hell of a Wham! Episode for a future season.
 * During A Scandal In Belgravia, John says something along the lines of "I don't know if anyone's interested, but I'm not gay!".
 * ...and then a certain someone informs him that, and implies that John is in the same boat. And then John looks like he's been thrown for a loop. This on the heels of him  . So it's true that we now have an instance of Watson saying the magic words, but they seem less magic in context.
 * As a point of fact, John could still be into Sherlock and be telling the complete truth when he says he's not gay. Being bisexual and being gay are two very different things.

Moriarty is Anonymous in his downtime. ALL OF IT.
Kind of obvious, really. Or Loliarty.

Moriarty doesn't have
He has

It would save money, and Moriarty has just the right sense of humor for that.
 * Alternatively, he might have It could be a clever.
 * We know he has at least one
 * For the crack, let's say that . This would make for an... interesting development.
 * Not so crack if we assume that Sherlock is clever enough to know that
 * For more crack, the bomb was fake.

Moriarty isn't really
Even with British Brevity in play, it's way too soon. And it seems odd, and possibly Out of Character, that the Man Behind the Men would show himself like that. So is a fake, either arranged by the real Moriarty as a "public" face or operating on his own without the real Moriarty's consent.
 * sounds like a nephew's name, to a Professor James. So he is a Moriarty. Just not the Moriarty.
 * The credits at the end of the episode don't list his last name as "Moriarty". It just says "". So Yeah.
 * Didn't the canonical Moriarty have a brother also called James?
 * It was his name and his brother's name. Doyle was consistent like that.
 * An older brother, the real mastermind, who is a famous physicist (like Brian Cox), played by Cillian Murphy.
 * Which would be brilliant for parallels, too. Sherlock faced off with the younger brother. The younger not-quite-as-clever Moriarty against the younger, not-quite-as-clever Holmes. Wouldn't Sherlock just hate that?
 * The old lady said that the man who captured her had a soft voice. voice was not soft.
 * The Hounds of Baskerville seems to support this theory.
 * Actually, that seems to be Mycroft agent,who is letting him out under his order for the trial in "The Reichenbach Fall".
 * What trial? And if Mycroft has the real Moriarty in his hands, why wouldn't he just have the man shot in secret?
 * See the preview here. It also confirmed that his name really is James Moriarty not Jim Moriarty.
 * Jim is a common nickname for James. James would be used in the presses, Jim would be used personally.

Anthea's real name will end up being Mary Morstan.
First Girl Wins, after all.
 * In A Scandal in Belgravia, Also, John was not displeased to see her again.
 * Anthea was not in "A Scandal in Belgravia."
 * I see this as a possibility if you rely solely on Arthur Conan Doyle's canon (in which Mary is given no characterization other than the name of John's wife). If you're looking toward movie/series canon from over the years though, then the chances are slimmer.
 * Mary did get characterization in The Sign of Four, which introduced her. She was a sweet, extremely nurturing woman, somewhat melancholy due to a troubled past, and smart enough in the way she presented the details of her case that even Holmes was impressed and declared that she had a "decided genius" for "such work". Sadly, she never really came in again, only making a few cameos, and by the time of "The Empty House", . Considering the expansion in Sherlock on characters like Moriarty, Mycroft and Mrs. Hudson, it's not unlikely that Mary will be developed into a recurring character

The bomb jacket at the end of 'The Great Game' kills Watson and Holmes. And we get a better Life On Mars spinoff.
Cause Sherlock Holmes and Gene Hunt. 'nuff said.

Mycroft Holmes is this universe's version of David Cameron
Hey, they look similar. And if Sherlock doesn't pay attention to the news, he could be forgiven for thinking that Mycroft still occupied a "minor position in government". And John just assumes its a lookalike.
 * Sherlock doesn't seem to believe it when Mycroft claims that. At most, he believes that Mycroft's official title is that of a low-level bureaucrat when he actually has a great deal of power.
 * Like such.
 * What if, instead of being Cameron, he is Lord Peter Mandelson (very british case of The Man Behind the Man )?

Sherlock is an AU version of L.
They're both tall, skinny uber-genius detectives with dark hair that have a hard time living with "normal" people. Fans have noted that the way they sit in couches (unaired pilot in the suitcase scene, Great Game where he insults bad telly) is awfully familiar. Also, Sherlock is surprisingly good at fighting. Of course, Rule of Funny demands that  is Light Imagay.
 * Reverse the polarity of the causation flow. L was, in no small part, based on Sherlock Holmes.
 * Sherlock's smile frequently provides a perfect real-life version of L's cat-smile.

Mycroft's umbrella is a weapon.
It's why he always has it with him, even when the weather doesn't call for it. It's not a sword-cane or anything like that. Instead, it has injectable poison darts in the tip, like the umbrella used to kill Georgi Markov.

Jim and Molly are actually siblings, both Moriarty.
Molly is the criminal mastermind, Jim is her devoted brother who acts as a catspaw when necessary. Molly asked Jim to do the whole "scaring Sherlock" bit, so that Sherlock would become obsessed with Moriarty but also be looking for the wrong person. Jim did it, but then decided on his own that Sherlock was now too much of a threat to both of them. It's a play on how canon is inconsistent over whether James is the mastermind or his brother. If I remember well, the envelope addressed to Sherlock in the Great Game was written by a woman, presumably an associate of Moriarty. Could be Molly.

Mycroft is Moriarty.
That Red Herring in the beginning was no Red Herring at all, but clever Foreshadowing. Mycroft is actually even bigger sociopath than Sherlock, but much better at keeping it a secret. He's moonlighting as a master criminal in order to reveal holes in the British police system and intelligence services. He decided to finally involve Sherlock since he really is concerned for him, and figures that only a real archenemy can make his quirky brother happy.
 * So Jim is...?
 * Just another hireling, of course. Should be clear without further explanation, with all these speculations that Jim isn't the real Moriarty because that would be too simple. Perhaps he actually killed that boy all those years ago, so Mycroft got him involved, so that Sherlock could find another "meaningful" link connected to himself.

Sherlock chose wrong in the first episode.
Sherlock took cabbies pill, instead the one that he was offered. Cabbie offered him Safe pill, on premise that "should take the poison from the hands of sage, don't take the cure from hands of foolish simpleton" (c) Omar Haym. He knew that Holmes won't trust a killer and would choose the wrong one.
 * After Watson shot the cabbie, why didn't Holmes just take both pills and get them analysed?
 * Because someone would surely ask which one he'd picked, and he wouldn't be able to dodge the question so easily, his ego simply wouldn't take it if he told someone, and he turned out to be wrong. Doubly so if the theory that both pills were poisoned is correct, because everyone knows Sherlock was dead serious about taking the pill, and that he fell for it would really prove he was fallible.
 * Upon re-watching, Sherlock demands to know whether he made the right choice, and before Sherlock declares that it wasn't important, the cabbie shakes his head (admittedly just slightly,) meaning Sherlock did choose the wrong one. All of the victims chose to switch rather than accept the pill they were given, the cabbie was honest in calling it a game of wits, because he understood that people under stress will switch in order to feel in control, that they are unlikely to sit back and do nothing. The question is resolved before Sherlock changes the subject and steps on the guy over the identity of his "fan."
 * I saw that headshake, and I always thought it was, "No, I'm never going to tell you," not, "No, you chose wrong." But it could be that, given the way Sherlock immediately changes tack.
 * I concur with the above troper; the headshake is a refusal to tell. But I also agree: Sherlock chose wrong. Why? Because. 1. Sherlock's great gift is the ability to deduce incredible amounts of information from tiny details. 2. The cabbie's great gift is the ability to, in his own words, understand how people think, how they think he thinks, and how they think he thinks they think. 3. Sherlock had to ask. That's the key point. This is a match of their two gifts, and Sherlock's gift has no uncertainty about it. That means his gift failed, and the cabbie's won out. The cabbie really did create an impossible puzzle to solve.

Neither pill was poisoned.
Neither pill contained any actual poison. The pills in question were some type of medication the cabbie was using to stay alive. It just so happened that what was keeping him alive (lowering his blood pressure, thinning his blood, etc.) would kill a healthy human.
 * So really, they were both poisoned.
 * Both pills are poison... if you don't happen to be suffering from the cabbie's medical condition. So no matter which choice each one chooses, the victim gets the poison, and he gets the medicine, which proves that the cabbie is smarter than his victims. Never go in against a Driver of a Black Cab when death is on the line! HAHAHAHAHABANG
 * So you're saying the cabbie spent the last three years building up an immunity to the poison?
 * Not really. Let's say that after he was diagnosed with a brain aneurysm, his doctor prescribed him some hard-core blood thinners. He takes them, he clings to life. One of his victims takes them, their blood gets so thin it prevents oxygen from getting to the brain and *thud*.

There are not really dozens of snipers, and the multiple laser points are some sort of trick.
told Holmes that he didn't intend to kill him then and there. In the context, he could have meant that he wouldn't kill him that very instant but the second appearance was fair game. Really though, seems more like the sort to play with his food instead of eat it. If he kills Sherlock now, what fun would that be for him? Furthermore, clearly enjoys playing sick mind games.

This troper's theory is that there is only one sniper, or perhaps none at all. The multiple laser points are just trickery, maybe caused by mirrors.

The Golem is The Slender Man
Just look at him!
 * There's that whole problem of him having, you know, a face. And an actual identity. And needing to strangle people rather than just mindrape them to death or dissecting them and putting their organs in bags.

The Golem is Agent 47.
Tall, lanky bald man who wears a suit and kills people for a living? It has to be!

John has nine lives.
Sherlock is the work of two Doctor Who writers. What would you expect?

Mrs. Hudson will become a Memetic Badass In-Universe
Why? You mean besides Rule of Cool? Alright. Sherlock is a hard person to get a long with, but Mrs. Hudson has managed to survive him and his experiements, and while she complains, she never has actually threatened to kick him out. That can easily be handwaved away by her being friends with Sherlock, but In-Universe, who would belive that? Instaid, it would probably be easier to believe that she is much more Badass than she appears, both by the coppers and by the people who read John's blog. And it will have nothing to do with the Kink Meme where she's going to end up a ninja zombie killer somehow.

Moriarty is Red John
Soft voice, short brown hair, under six feet tall, intelligent, psychopath who likes to play games.

Moriaty is a clone of the The Master.
I'm sick of all these time lord theories, let's say that the 2010 version of the person who hired him to steal the Mona Lisa in the Jeremy Brett series found the remains of the Master, (assuming that he died at the climax of End of Time) and used them to create the criminal mastermind.
 * You say you're sick of them then write another. ...what.

Sherlock is Artemis Fowl, all grown up

 * And Mycroft is Myles, whose more moral upbringing led him to government work.
 * Which would make Beckett Moriarty, I suppose?
 * Nope. Opal Koboi is Moriarty. ...Try not to think about that too hard.
 * Or Artemis is Moriarty; he went back to his criminal ways. He has the right accent after all.

The gun is empty.
In the third episode, Sherlock fires several shots in the house when he's bored. Later, when he and John go to confront the Golem, John realizes he forgot to put more bullets in before they left, but there's still enough ammo for Sherlock to get off a couple of shots. It's possible, and really probable, that Genius Ditz Sherlock also forgot to reload the gun before he ran out to  Therefore, even if Sherlock does   nothing will happen except there'll be a tiny, empty click.
 * "But doctor, it just doesn't make sense! Thousands of people have heart attacks every day, but never all at the same moment! And the only thing they had in common was ... a TV show!"

Mycroft Holmes is an angel's vessel.
It's why his relationship with Sherlock is so negative; it's not a childish feud at all (notice that when John asks if it really is a childish feud, he doesn't say yes). It's not Mycroft that Sherlock is "so resentful" of, it's the angel; in reality, he hasn't spoken to his brother in years. In that same vein, Moriarty is either possessed by a very powerful demon or is consorting with them, and both Sherlock and "Mycroft" know it, and are trying to bring him down. Take this into account, and some of the dialogue takes on a new meaning.
 * "It's time to choose a side, Dr. Watson."
 * "Did it ever occur to you that we belong on the same side?" "Oddly enough, no."
 * (Concerning Moriarty) "What are we dealing with, here?" "...Something new."
 * Suddenly, the dialog on the hospital's roof about the sides of angels and demons also starts to make sense. Maybe too much sense.

Sherlock was bullied as a child.
Think about it: Sherlock is incredibly smart, socially inept (unless he's acting), and is explicitly stated to have no friends. In fact, the bullying might have even lead to his work of capturing criminals. Also, his reaction to John saying that he was fantastic is met with surprise. This tells us that he's not used to people being happy about his ability.
 * And probably well into his teens, watch his face in The Blind Banker when Sebastian tells John how all the kids at uni hated Sherlock.

Sherlock isn't asexual; he's demisexual.
He's just never been close enough to anyone to form an emotional connection, thus, no opportunity to form a sexual attraction.

'The Reichenbach Fall'.
The title of the upcoming story actually refers to three falls, Jim who will be a fall guy for the real mastermind, Sherlock will fall for the ruse and thirdly Jim will die by falling.
 * They've already had two fake-outs regarding Moriarty's identity (Mycroft and Jim from IT). A third would result in massive eye-rolling from the audience (plus it would completely gut the scene at the swimming pool).

Mycroft hired Sarah.
At the end of A Study in Pink, Mycroft says "increase surveillance to level 3 on Sherlock Holmes and Dr. Watson" (or something to that effect). But in the other two episodes we see nothing that reflects this increased surveillance. Then we have Sarah Sawyer, who really has no reason to be dating John. He didn't make that great of first impression. So why would she go on a date with him? Simple: Mycroft hired her to spy on John and Sherlock. Though I suspect she'll be revealed to have fallen in love with John throughout it all anyways. Unless she's not the Mary Morstan stand-in that she appears to be, which would make for an interesting development.
 * She certainly appears to have hidden badass qualities that seem a little unusual for a mild-mannered doctor. But then, John has hidden badass qualities that seem a little unusual for a mild-mannered doctor. It's implied that her initial interest in John was sparked by his military history; she's either got a man-in-uniform fetish or, more likely and more like John himself, she's a bit of an adrenaline junkie and thrives on danger. Hence why she keeps dating him after That, and yes, Mycroft could be paying her. He's not above paying people to spy on Sherlock, why would he be above paying people to spy on John as well?

The datastick was empty.
Do you really think Mycroft would let Sherlock sell out secrets to criminal masterminds? Either the USB was empty, or the plans on it were fake. Moriarty knew that, so he threw the "plans" into the pool. And it's not like Sherlock couldn't have brought it up with Mycroft; they met before the pool incident, and Mycroft brought in backup, just in case. They haven't arrived yet, but they will.
 * Moriarty threw the plans in the pool because he "could get them anywhere". He only cared about them in the first place as a tool to get Sherlock's attention. Also, it's pretty blatant that Sherlock was lying when he told John he'd seen Mycroft.
 * Sherlock appears though to honestly not know that Moriarty could have gotten the plans anywhere and that they were a red herring. Although he may or may not have really seen Mycroft in person, it still seems unlikely that Sherlock would be dumb enough to offer a criminal mastermind some real, unaltered missile plans that could potentially begin World War III when he could offer him a wiped memory stick or some altered, useless plans. After all, unless Moriarty had brought his trusty laptop with him and checked them then and there, why give him the actual plans? He'd be long gone (or at least not present) when he figured out the plans were fake.
 * But if there were no real plans then why would Mycroft send Sherlock after the fakes? And how would the murdered man not realize they were fake?
 * I never said there were no real plans. Just that by the time Sherlock gave the "plans" to Moriarty, he'd tampered with or switched out the memory stick so that the real plans were no longer on it. It was either blank or had been switched out for fake plans that meant nothing.

The death of the old woman in 'The Great Game' was planned.
As another troper pointed out in an above post, she described her abductor's voice as soft- whereas Moriarty's voice is not at all soft. Moriarty wrote it into the script so Sherlock would buy the reason for her death- when in reality, he did it to destabilise Sherlock, and possibly trip him up or make him make a mistake.
 * My interpretation is that the death of the old woman was Moriarty proving to Sherlock and everyone else that he meant business and was in control and not to be messed with. After all, if Moriarty "played fair" then presumably the old woman would be rescued and tell her rescuers about the "soft voice" anyway. And of course, on a plot level, it was to prove to audience members that the threat to the hostages was real and not a bluff (makes the next two hostage situations that much more frightening- this guy has killed before, and a helpless victim at that, he would theoretically do anything.) It wouldn't have really mattered what she'd said or not said, Sherlock was always going to "lose" that round. After all, Moriarty easily gets bored and probably wanted to spice the game up a bit. Also, indicates that he doesn't play fair and is "changeable."

Anthea is a Tetris addict.
Why not?
 * She's certainly addicted to something. Angry Birds?

Sherlock will fake his death at the end of "The Reichenbech Fall" because he's gotten too famous to operate properly

 * The opening of "A Scandal in Belgravia" is all about this, it was the real world reason why Conan-Doyle did it and Moffat's already made it the central theme of Doctor Who Season 7.
 * Confirmed, somewhat.

1895 will turn out to be a code, password or some other form of secret message. Just not from Irene.

 * Personally, I would have trouble NOT using it as such as soon as it was mentioned to be stuck like that.
 * Me and a friend of mine started trying to crack the code and found a possible solution- in the poem "221B" by Vincent Starret, he says "and it is always 1895". 1895 is used as a generic period in which Sherlock Holmes's stories are set. If you think that Sherlock said something along the lines of "it's frozen at 1895" (or, in other words, "it's always 1895"), it could just be an in-joke. Of course, that'd be so anticlimatic I might die a little inside, so...

Irene is dead
This was actually my first thought in watching the episode. At the end of A Scandal in Belgravia, Sherlock can tell John is lying about Irene and knows she's dead. The apparent flashback is actually just Sherlock deducing what happened to her and how he could have saved her.

Mycroft knows that Irene is still alive
Mycroft is a practical man. If he wants John to tell Sherlock that Irene is alive in America, he tells him that she's alive in America, he doesn't add "actually no, she's totally dead. Now keep this horrible horrible secret that will emotionally destroy my brother and never mention it to him". While he doesn't seem to know John that well, it doesn't take a genius to imagine that the guy might feel guilty and tell Sherlock the truth- and even if he doesn't feel guilty, would he take the risk? Hell, for all he knows, John might blurt it out in a drunken night. Also, John isn't a good liar. Sherlock has picked this up, it's likely Mycroft did as well, and would know that if John tried to tell Sherlock the lie, while knowing the truth, Sherlock would read John like a book and figure out the truth in 2 seconds flat.

So, why did Mycroft tell him that Irene is dead if he didn't want John to mention it to his little brother? Because they can't have easy things, that's why. Hear me out: if Mycroft were to tell John that Irene was alive in America and nothing else (the most sensible thing to do), John wouldn't be all nervous and guilt ridden while telling it to Sherlock, leaving Sherlock to raise an eyebrow- what, his brother doesn't know that a terroristic cell tried to kill Irene? What is he trying to hide?

By telling John that she's actually dead, however, he can be sure that he's going to act all weird and nervous (that's what people with feelings and stuff do): Sherlock would of course note it, and understand that he knows (thinks) that Irene is dead- something that only Mycroft could know. That leads to the obvious conclusion- that Mycroft and the Government think that Irene is dead, that they will leave her alone etc.

So there it is: Sherlock is happy 'cause he fooled his older brother, and Mycroft lets him think that while he keeps following Irene closely.


 * I disagree with the central premise; Mycroft had every reason to ask John. Despite being his brother, it seems clear the Mycroft simply doesn't know his brother as well as Johndoes. Oh, sure, he knows some. (That's why he can opine that 'tonight's a danger night' earlier.) But how he'll react, what's actually going on in his head? Mycroft's deferring to John. It's a smart play. Sherlock fooled them all.

Reece Shearsmith will appear in one of the next episodes.

 * It would be awesome and he's perfect for this series and half of the League of Gentlemen would be reunited. And, after all, Shearsmith and Pemberton did call Mark Gatiss for an episode of Psychoville, so he owes them one. Hell, considering they're friends, isn't the fact that Reece Shearsmith didn't play Moriarty a Missed Moment of Awesome of epic proportion? And wouldn't he make an awesome Sebastian Moran?
 * Yes Yes Yes Reece as Moran YES PLEASE!!

Irene's death in Pakistan by the terroristic cell was actually Mycroft's plan to get rid of her.

 * And Sherlock followed them because he knew his brother was going to do something like that, which is the reason he found himself disguised as a terrorist to save her. I think it's a good way to connect the final events of ASIB, and it explain what Sherlock was doing there, since I'm pretty sure he has other things to do than follow Irene's every moves instead of just assuming she can protect herself without his help. And Mycroft, the Iceman, probably just though she was way too much trouble.

The "terrorists" who capture Irene at the end of Scandal are actually British agents.

 * It is unlikely that the terrorists who were planning to blow up the plane would target Irene. Her actions let them know that the British government had deciphered their code. In other words, she helped them. The British have much more to gain from Irene's death than the terrorists.

Sherlock and Irene had sex at some point after her rescue.

 * I'm not saying it's plausible, but something about the way Sherlock chuckles to himself and repeats "the woman..." leaves room for speculation.
 * Actually, this is a reasonable possibility. Sherlock rescued her out of emotion, not logic or practicality. Having discovered that he is capable of feelings, he might decide to find out why people make such a fuss about sex. Purely in the interests of science, of course.

The next three stories will be...

 * "The Empty House," "The Blue Carbuncle," and "The Valley of Fear."
 * "Silver Blaze," "The Blue Carbuncle," and "The Devil's Foot."

Tumblr is going to crash after The Reichenbach Fall airs.
There will just be too much flailing for the server to handle.
 * That's not even wild guessing, the Tumblr Sherlock fans feel an incessant need to make a jillion posts repeating the same thing over and over. What would be a wild guess would be if they crashed it with something actually worth posting...
 * So far Tumblr's fine, if a bit hectic. Omegle, on the other hand, has more Sherlock questions than porn. PORN.

Sally Donovan is a Corrupt Cop and Sherlock dosn't know it yet
She's trying to get Lestrade to stop contact with him before she is exposed. By calling him names, she thinks she's going to make him feel unappreciated so he'll just go away, not knowing that Sherlock's too obssesed with not being "bored".

The CIA agent who attacked Mrs. Hudson got off lucky.

 * The last person to do that, Mr. Hudson, ended up on death row in Florida. Possibly after being tossed out of several windows.

Sherlock's mind palace is not a palace, it's London.
As evidenced in Study in Pink, he knows every street in London. Now, how could he make use of a virtual map of London in his head (apart from chasing taxis and looking clever after being kidnapped)? To store all his codebreaking trivia in there, of course!

Real-world memory champions have memorised huge amount of houses and palaces and whatnot just to use as memory palaces. The next logical step for a genius like Sherlock would be to use a whole whopping city and organise the data around the boroughs and districts.

There is a connection between John's hitcount being stuck and the morse code.

 * Attention has been called to both, explanation has been given to neither. If another such thing happens in Reichenbach, I will be justified to use the phrase "Once is happenstance, twice is coincidence, three times is enemy action."
 * The code Jim taps and the "IOU" he leaves Sherlock are both red herrings. Does that count?

Sherlock hurled

 * There's Fridge Logic aplenty with this guess, but my puny, un-Sherlock like mind is struggling to guess what really happened.
 * Good idea, but John saw his face after he landed. Also, wouldn't Moriarty's observers notice the change of clothes?

The cyclist was one of the Baker Street Irregulars

 * Sherlock makes light reference to his own network beyond the police. During the final act, he knew that Watson was so he used one of his crew to stall him while he  The mechanics of the last bit...who knows?
 * Well, Sherlock was adamant that Watson not move forward; doing so would have moved him in front of the cyclist, plus there was quite a distinctive noise at the collision (audio cue?). It is definately important.

Sherlock's

 * First, when Sherlock told Molly he needed her, he was asking for her help to . The crowd around   was actually switching   for a fake

Sherlock needed Molly to send some messages
Alternatively...
 * Moriarty only had three snipers: one for John, one for Mrs Hudson, one for Lestrade. He thought those were the only allies Sherlock had. He had no idea Sherlock trusted Molly - after all, he'd dated her and hadn't found her to be anything special. Sherlock knew Moriarty wanted him to  - not to mention at least three minions waiting for it - and he also knew he had people who could help him fake it - Mycroft, for one, seems more than capable, and  . All he needed was someone to get messages to the right people. Someone Jim wouldn't be watching for. Step forward, dear little Molly...

Sherlock needed Molly to describe Jim

 * He'd already worked out Jim would have snipers trained on his friends, and he also knew Jim had a 'stop' command. Molly actually knew Jim for longer than Sherlock did and although she can't Sherlock Scan at all it's possible that with a good enough description Sherlock could Sherlock Scan him without him being there. Once he knows what sort of man Jim is, figuring out the stop command becomes easier. Then he just has to taunt Jim into  so Sherlock can pick up his phone and send the command. Once the pressure's off, he can work out a clever way to   so as to avoid the wrath of Moriarty's minions.

Moriarty is also

 * He'd put a lot of effort into this endeavour for no reason other than to screw with Sherlock. And we're supposed to believe he  before he got to watch the big payoff? It's not like The Sociopath not to stick around to be proved right, and it's not like a Psychopathic Manchild to leave before he's finished all the fun. Plus, screwing with Sherlock isn't even all he wanted - he's still got Mycroft 'The Iceman' Holmes as a more-than-worthy nemesis. Basically, the guy had   to make it believable. And we didn't even get that clear a shot of  . We saw him   Nothing a man of Jim's intellect can't work around. Also... Stayin' Alive?
 * Could Jim work around Sherlock watching him fake suicide? He's supposed to be Sherlock's equal and so letting him once again win at everything would be - as Jim himself said - boring.
 * Maybe Sherlock knows that Jim, and incorporated it into his plan. That could be why he had to tell John he was a fake; he knew Moriarty was   listening. Either way, Jim's   wasn't reported to the public, else the newspaper headlines would have been about a.
 * Plus, Moriarty has already beaten Mycroft, in a way, with not cracking under interrogation.
 * And he got Mycroft to end up helping him destroy his brother. How much more could Mycroft possibly be beaten?
 * Possible. All Moriarty would have needed was

The writers have read the numerous "Jim isn't Moriarty, X is" theories

 * Which is why a big part of Jim's plan in ''The Reichenback Fall
 * Actually, it is yet another call-back to the original stories. The notion that Moriarty never existed is one of the oldest WMG's in the world (In The Final Problem we, or rather Watson, never meets Moriarty, only hears about him from Holmes.)

The stop command for Jim's assassins was "IOU"

 * Jim's the sort of man who'll use "Rich Brooke" as a psuedonym just because it cross-translates as "Reichen Bach". Of course he'd already told Sherlock all he needed to save himself. The game wouldn't be fun if the opponent didn't have a chance. 'IOU' is the only message Jim gave Sherlock that wasn't explained as being for some other similar mind-game purpose.

Alternatively, the command was "Snipers no sniping!!
Just because.

Molly is the teselecta
Obviously Sherlock deduced that she was a fugitive from Doctor Who and when he said he needed her he specifically wanted inside for the purpose of faking his death. Sound familiar?
 * ...what? What has the Teselecta got to do with fugitives? Aren't they a justice department of some sort?

How Sherlock
Calling it right now:
 * I was thinking something similar, but
 * For all we know,
 * In the Baskerville episode, they mentioned they were doing human cloning...
 * The EMTs who show up immediately are not really EMTs. Unless it's Artistic License.

The series' Jim Moriarty will become a Legacy Character.
In Doyle's original works, both the famous villain and his brother were named "James Moriarty" (Doyle wasn't too concerned about consistency). It makes sense that for the series, another person calling himself Jim Moriarty will appear.

The tabloid journalist was employed by Moriarty
You'd have to be pretty daft and/or blinded by vindictive rage to think that a person who accurately Sherlock-scanned you the minute you met was. And would Moriarty trust a key part of his plan to to a person he couldn't control? Remember, that reporter was at the trial where a jury under the most suspicious circumstances imaginable. Any journalist worth their salt would be all over trying to find out why. Corruption in the trial of the century? That would be the scoop of the century! And any journalist who did get even a single member of the jury to talk (granted, would make that difficult), would provide evidence that Sherlock. It makes much more sense if she was hired, coerced or (carrot and stick) both. "You hate Sherlock Holmes for spurning you? "
 * Then again, Sherlock did deduce that she wasn't all that clever, which is why she hadn't yet hit big. I'd find it most likely that she was so desperate for a huge scoop that she took the first chance she got without giving much attention to checking out the facts or journalist integrity beyond the most basic check of "Rich Brook's" background. Over time she might have figured out the inconsistencies, but by then she would have to publically admit that she did not do the research, and lose her fame, professional reputation and job in one fell swoop, which someone with her personality is very unlikely to do.
 * I doubt any juror would be willing to talk, even if promised anonymity. They all threw the trial for Moriarty so they'd all be too scared to share the information. And anyway, Jim did an extremely good job of creating his fake background. He has so many real details about Sherlock from Mycroft to give his story weight, he probably has been playing Richard Brook since Sherlock got that nickname, and he's good enough to forge the rest of the documents. If it were just a matter of the reporter being stupid and vengeful than it wouldn't have been so difficult to clear up.
 * In our real world, or one as close to it as Sherlock is, Moriarty's ruse would not hold up. either, or
 * The thing is, though,
 * Or, alternatively, Moriarty's brother (who in mentioned in cannon) takes up the job of keeping the Richard Brooks facade going. In the original stories, he makes it difficult for many people to believe Moriarty was guilty of anything.

Sherlock thought the
The only people who'd think that a few dozen bits -- barely enough to write a few characters in ASCII—is a magic code which can unlock any computer anywhere are Hollywood executives.

Lestrade will be
He's known Sherlock for years, and he has much less antipathy towards him than most members of the police force do. More than almost anyone else, he's seen Sherlock doing. And, being neither vengeful nor Flanderized into foolishness, he can see that. He'll eventually be alongside Watson, Molly, Mrs. Hudson and a host of people whose cases Sherlock solved wearing the "I'm Sure About Sherlock" buttons.

Sherlock is not a sociopath, but is autistic.
Sociopathy doesn't seem to fit. Not to mention, there is no such thing as a "high functioning sociopath" like Sherlock called himself in the first episode. He likely just wanted to say something to get on Anderson's nerves. There IS, however a type of high functioning autism, or Aspergers. He has trouble connecting to emotionally to others, but it's clearly not impossible as evidenced by his attraction it Irene and his friendship with John (something that Asperger sufferers CAN do). The biggest evidence though, is in 'Hounds of Baskerville' where John tells that Sherlock is secretly pleased that he's there,  seems surprised but guesses that it's because familiar faces help Sherlock feel more comfortable, but has trouble expressing this (not something that a sociopath would need). then struggles for the right word and John says "Aspergers?".

Irene Adler
She has the most practice out of the entire cast at this sort of thing, after all.

The body in
"You are me", indeed. The video on John's blog seems to indicate that  body was never found, or else it would have been mentioned in the news report. After, Sherlock would be left with two problems:   Why not kill two birds with one stone? Also this could pave the way to a potentially funny (or at least definitely in-character) scene in the "Empty House" episode;

The Sherlock Holmes books do not exist in the Sherlock universe.
Honest, if Arthur Conan Doyle had written the novels, I think that Sherlock would have been asked about his name so many times that probably he would be used to saying "Yes, like the books" whenever he said his name to someone he doesn't know.
 * Um, yeah. I thought this was obvious, and I think It's even been said by the creators.
 * Or it could be that the universe is no longer aware they exist....which brings me to the silly guess......
 * To coincide with this, Sherlock!Doyle was still as famous as Reality!Doyle. Instead of being mostly known for writing the Sherlock Holmes stories, people know him for his series of books focusing on a man named Professor Challenger. The Professor Challenger series would go on to spawn a number of adaptations and spin-offs, including a Granada series, a film focused on his youth entitled Young George Challenger, and eventually a modern BBC series simply entitled Challenger.
 * But then what would Challenger!Doyle be known for?

The Sherlock Holmes books exist, but in a similar situation to ABC's Once Upon a Time's Storybrooke.
There was a curse placed on all the characters of the Sherlock Holmes books. The books exist and the characters are real, but because of the curse, they have forgotten and so has the rest of the world. Though where Storybrooke's curse forces them to be separate from their past lives and be unhappy, their curse forces them to relive their lives as the books have told. Moriarty is the only one who knows, which is how he is able to orchestrate everything perfectly and is so bored because he knows what's going to happen

The vacuum left by the removal of the Sherlock Holmes canon from popular culture was filled by Sexton Blake.
As a result, in the world of Sherlock, stupidly stating the obvious is met with the phrase "No shit, Sexton".
 * I'd been thinking "No poo, Poirot."

How Sherlock appeared to have no pulse
I don’t know how Sherlock managed to jump without seriously hurting himself (other than just letting his body go limp before it hit the ground would have lessened the impact damage). However, it’s a relatively simple magic trick to make to seem like you have no pulse. All you have to do is
 * Sherlock was playing with  in an earlier scene in the lab...
 * Holy Shit. *Mind is blown*

Mycroft played Moriarty and Sherlock completely
Mycroft is smarter than and regularly manipulates Sherlock. He knowingly played into Moriarty's obsession and gave him everything he needed to take Sherlock down, knowing Sherlock would destroy Moriarty. He also uses John, manipulating Sherlock through him.

Sherlock intended to become a criminal, but changed his mind
Mycroft tells us that he wanted to be a pirate, and he's good at pick pocketing, which is an acquired skill, not something he can do just out of smartness, so he must have practised. He may even have started out a criminal career, but changed his mind when he realised that it wouldn’t give him the acclaim he needs.


 * And he knows how to pick locks really well too. And seems to have no aversion to torture either....

John was drugged with the hallucinogen from The Hounds Of Baskerville at the end of Reichenbach Fall
The phone call at the end of the episode seems deliberately cruel, given that Sherlock  - he could have sent John in the wrong direction, making sure that he saw nothing. There wasn't much he could do about the risk factors anyway, so why have John watch the whole thing play out? Assuming that Sherlock's tears are genuine (nothing is certain with that bloke), it tore him up to do it. Why make a point of telling John to keep looking at him? . Presumably, this served as a backup plan if John arrived on the scene at an inopportune moment. If John is cornered and pressured for information, he can say, without a word of a lie, that he saw. The incident with the bike further served to disorient John, and prevented him from seeing what was really there.
 * I agree, and add this: the last time John and Sherlock are together, in Bart's lab, John is napping and his phone is sitting on the counter near him. Sherlock could easily have . Then, later, he kept John on the phone as long as possible . The biker could have been one of Sherlock's homeless network, . It's already been shown that Sherlock likes to keep souvenirs of old cases (the spray paint from "The Blind Banker") and it would be just like him to steal a sample of the "Hounds" drug (at the end of "Hounds," he remarked to John about the leakiness of the pipes in the lab that were spraying the drug into the air, he obviously was in that particular room at some point and could have bottled some up). Plus, "Hounds" established that the camera "sees" what the drugged characters see, so in "Reichenbach" we would have seen, because that's what John saw.
 * Or, alternately...

Both John AND Sherlock were on the H.O.U.N.D hallucinogenic

 * It seems much more Moriarty's style, not getting his hands dirty, letting the drug do the work, much more high-risk, but much more fun, to screw with Sherlock and John.
 * The whole story-teller-Moriarty-cab-scene seems nightmarish, but its not just that, at the end and the beginning, the movements Moriarty makes (During the glitchy patches) are oddly similar to the one Sherlock hallucinates him doing during Baskerville.
 * Moriarty wasn't even driving the cab, Sherlock imagined that too.
 * Not only were cameras hidden in Baker street, so was the H.O.U.N.D drug, hidden everywhere that it might be admitted into Sherlock and Johns blood stream.
 * It's even possible that the entire roof-top scene was hallucinated by Sherlock (We've already seen that the drug can drive people insane) causing him to go bat-shit and throw himself off Barts.
 * That's why on John's blog, there's no mention of Moriarty's body, because Moriarty wasn't even there.
 * John Hallucinated the call about Mrs Hudson being shot as well.

John will rejoin the army after the events of the last episode.
Sherlock was not only John's best friend, but also a way for him to stop being bored. Because he was discharged from the army due to injury, John might end up in Afghanistan or Iraq as an advisor or desk jockey as opposed to an active soldier, but because the limp was psychosomatic, you never know.

And so the third season will involve Sherlock showing up in the Middle East to save John and his unit from an IED - or John saves a disguised Sherlock from a similar fate. Alternatively, Mycroft will recall John back to England.

Before meeting Jim on the roof of Bart's, Sherlock arranged to send a signal to Molly by mobile phone.
He sends Molly the signal during his "moment of privacy" when Jim's back is turned. During that moment, you only see a head-and-shoulders shot of Sherlock so you can't tell what he's doing with his hands, but listen carefully for the sound effect.
 * There really IS a brief click which may or may not be him sliding his phone open. Well spotted, good sir/madam.

Sherlock's callous treatment of Molly in previous episodes is because he was keeping her Beneath Suspicion for precisely this sort of situation.
Considering that Jim had Mrs Hudson as one of his targets, he would almost certainly have targeted Molly too, on the slightest suspicion. But Sherlock always knew Molly would be a useful ally if the need arose, so he deliberately maintained the facade that he barely noticed her existence. Even John couldn't suspect the truth, in case he let it slip to Mycroft.

Moffat and Gatiss have a watertight explanation of how Sherlock survived, but have no intention of telling us what it is.
Season 3 will tease us with a series of tantalising hints and unreveals instead.

Whoever Sherlock fingered for the Reichenbach Falls painting theft, was just Moriarty's fall guy.
The events of the episode cover three months - which doesn't seem time for Jim to establish his Richard Brook persona. Ergo, he started establishing the Richard Brook persona before Sherlock "solved" the theft, meaning he was behind it and led a false trail of clues (to either a terrified accomplice on whom he pulled the "if you want your family to live" trick, or an innocent party) which Sherlock fell for.

Sherlock has a Portal Gun.
That's right.
 * But he'd keep his momentum regardless... what he really needs is those fancy bouncy shoe... things.

Moriarty had a body-double made of Sherlock.
We cobbled this one together after watching the episode—and if they've come up with something that is more convoluted and brilliant than this, we can't even imagine it.

First, Moriarty had a body-double made of Sherlock. He was the one to kidnap the kids—that's why the girl started screaming when he came in, because he looks like the guy who kidnaped her.

Sherlock figured this out, tracked down the double, and killed him. He had Molly bloody him up to look like he just fell from a building (or did it himself), fitted him out with his clothes, and put him in the dumpster under the building.

When he jumped, it was into the dumpster (where there's something soft), tossed out the bloodied body-double, and then let things take their course.

Another component of this (that I didn't agree with) involved the Baskerville gas, which John was sprayed with by the biker. Which is why he was disoriented. I just didn't see any gas being sprayed, or a hint at it, so I didn't think that was likely.
 * I would love this to be true, just so that I could see Benedict playing two characters in the same scene, a la the Doctor in The Almost People.

Sherlock is an Assassin
He just did a Leap of Faith into the truck. Moriarty, of course, is a Templar.

Mycroft and Moriarty were acting together against Sherlock
It's a crazy idea I know, but this is WMG... ... Mycroft not only gave Moriarty all the information he needed on Sherlock, he LET HIM OUT. While apparently believing that he has the key to any electronic system, which given his other abilities, resistance to all Mycroft's interrogation methods, and evil nature makes him the most dangerous person in the world.

So perhaps Mycroft did break Moriarty, and got Moriarty not only working for him, but fanatically loyal. Together, they brought down Sherlock. Throughout "The Reichenbach Fall", someone is manipulating people through computers (the jury and the vault guards). The episode would suggest that it's Moriarty, but it could just as easily be Mycroft. Mycroft probably has the power to do all these things, with his security clearance as "the key that opens all doors".

But why would Mycroft bring down his own brother? It's hinted in Watson's chats with Mycroft that there is something between Sherlock and Mycroft, a long-running sibling rivalry. Perhaps there is a lot more to it than simply stealing one another's toys; they are both very unusual, intelligent people without many morals, and might have done some very nasty things to one another.

Sherlock is not in on the plot, and in faking his own death has outsmarted both Moriarty (terminally) and Mycroft. The result of this WMG is that Mycroft, not Moriarty, is going to become Sherlock's nemesis in the next series, because after all he needs a new one.


 * More likely than you'd think. After all, since Mycroft practically runs the British Government, he's certainly powerful enough to shut down the paper-thin investigation against his brother and fire a certain biased pair of police officers if he wanted to. Something stinks.

Sherlock will take the job of Moriarty
Moriarty is dead, but how many in the underworld will know this? Surely his contacts will still be coming to him for work, and with it in the news that Sherlock had faked Moriarty, how hard will it be for when they go to meet Moriarty for Sherlock to meet them? He can't exactly go back to normal consulting detective life and has to get his fix somewhere, why not in putting his brilliance towards arranging crimes?

Next time John sees Sherlock, he WON'T avoid the nose and teeth
After all, he beat Sherlock pretty badly just for punching him - I can't see him reacting well to the news that Sherlock was alive all along... "Sherlock Hello, John. John *thud* Sherlock John?"
 * He'll faint first though. It'd be a good way for them to show how much of a shock it is for John as well as a Mythology Gag.


 * Frankly it would be even more funny if the encounter inverted the book as described above; rather than John fainting, he punches Sherlock out cold, and then has to revive him.
 * John won't faint: Lestrade will.
 * And John won't punch Sherlock out: Mrs Hudson will.

Moriarty is the one-man UK branch of Wolfram & Hart.
A paid consultant who helps people arrange their crimes and get away with them? And I bet he's got a law degree too.

Moriarty didn't create in just one day.
After killing Carl Powers, in 1989, he saw a similarly young and brilliant Sherlock investigating, and began planting seeds for Sherlock's downfall. For the next twenty-two years. He really did  Because he's that much of a Manipulative Bastard.

"Mummy" is M from James Bond
She didn't mean to be emotionally distant, but you try running a bloody country and keeping multiple 007s in check. And this explains how Mycroft got into the government, with good old fashioned nepotism. And yes, I know that the James Bond films exist in the Sherlock universe, but think about it: what better way to make people dismiss the truth than to make it into a movie? Better yet, MI 6 gets a cut of the profits, so the films help to bankroll national security.
 * This is so beautiful that I think I might cry. And I demand a Judi Dench cameo as Mummy in season 3.

The entirety of The Reichenbach Fall was a massive Batman Gambit by the Holmes brothers
Impossible to explain without spoiling everything, so don't read if you haven't seen the episode:

Mycroft has Jim in some creepy torture dungeon somewhere, trying to get information from him (this we can assume from flashbacks and the ending of the previous ep). They are clearly willing to use illegal methods here, but what they really want is for Jim to give them the info necessary to legally put him away for good. Mycroft has multiple private sessions with Jim where he trades info on Sherlock for info on Jim himself - but "only a little" (as explained in the ep). Mycroft doesn't want "only a little", he wants everything he needs on Jim. So, during these sessions, he uses his Sherlock Scan (we know he can do this from A Study in Pink) to build a psychological profile of the kind of man Jim is. Once he's got this profile, he talks with Sherlock in secret (while John is away shopping or something, I don't know) and they come up with a plan. Mycroft releases Jim (seen at the end of Hounds of Baskerville) knowing that Jim will go to Sherlock. Sherlock tricks Jim into feeling powerful and in control by deliberately making bad and occasionally OOC decisions (he talks about the little boy's kidnapping as if he was actually present, he gets in the first cab he sees despite knowing he's got men after him etc - this last is even something he orders Watson not to do in the books, which Moffat will know). He also finds the pocket-sized camera in his apartment and, for all we know, purloins it and finds a way to rig it wirelessly to a computer which Mycroft is monitoring somewhere. Then he lures Jim to the roof of St Bart's - a position deliberately chosen to make Jim feel even more powerful because it allows him to do the whole forced-suicide thing easily. While on the roof, in another OOC moment, he manipulates Jim into explaining everything, rather than his usual work-it-out-myself-and-tell-no-one-til-I-decide-I-want-to shtick. For all we know, he had planted that secret camera somewhere, and is tricking Jim into the villain monologue as an Engineered Public Confession - only not yet public; only Mycroft and anyone else on the other end of the camera connection see it. Then he manipulates Jim into suicide (or at least faking suicide. I mean, y'know, this is Jim Moriarty) and, as several theories above suggest, he leaps from the roof into the laundry truck below, jumping out while John is distracted by a cyclist (possibly also in on it) and faking death with fake blood, good acting and a rubber ball jammed in his arm to cut off his pulse (we saw him play with such a ball earlier, see several theories above). Some paramedics - also in on the gambit - cart him off to be declared dead by Molly (whom Sherlock has convinced to also become a part of the conspiracy - hence his "what I need is you" line) and identified by Mycroft (who is his next of kin after all). Sherlock remains "dead" for as long as it takes to convince Moriarty's men, thus avoiding any revenge-kills on their part. In fact, he and Mycroft possibly use this period of uncertainty among Jim's men to their advantage by tearing apart the network now that its queen bee has eaten his gun. Meanwhile, after a suitable amount of time that won't arouse suspicions as to how it happened so fast, Mycroft releases the video of Jim on the roof explaining how evil he was, and suddenly the public now loves Sherlock Holmes again. Jim's on-tape confession clears up any mucky loose ends surrounding his crimes and subsequent death. As far as the public and probably Mycroft's superiors are concerned, everything was legal and above-board, if unconventional. Sherlock Holmes reveals himself to be still alive, his suicide having been just one more part of the deception to bring down the now posthumously-reviled Jim Moriarty. Congratulations all round, Sherlock goes home to John and Mrs Hudson, Mycroft returns to the Diogenes Club safe in the knowledge that, with his brother's help, he pulled off the most complex sting operation of his career.
 * Holy crap, yes. (With the possible exception of Jim's suicide which I'm not sure Sherlock saw coming) but apart from that, holy crap, yes. This. This explains all. This had better be canon.
 * Adding to the above, Sherlock's "whole life story" is full of lies. Mycroft didn't give him real info on Sherlock. He made a lot of it up, which will mean that the Sun will have a lot of explaining to do after it's found that their expose on the "Fake Genius" couldn't even get his easily-checked details right. Another step in clearing Sherlock's name in season 3...
 * Look at the part where Mycroft tells John "I'm sorry... tell him, would you?" Now think of that line in a totally different context. John's just torn strips off Mycroft for what he perceived to be his betraying Sherlock to Moriarty. If the above Batman Gambit is true (and it seems likely) Mycroft never did any such thing, or at least, if he did so, it was with Sherlock's full knowledge and assent. "I'm sorry" sounds genuine; but Mycroft may not mean "I'm sorry for selling my little brother down the river", but "I'm sorry for my part in what you're about to suffer, John."

The Reichenbach Fall was a massive Batman Gambit by Sherlock.
To comment on the above WMG, while it's likely there is a big Batman Gambit going on, it seems that it’s mostly orchestrated by Sherlock alone. The Reichenbach Fall implies that Sherlock wants to completely disappear for two reasons: 1) he dislikes all the publicity he's now getting, and 2) he realizes his line of work puts the people he cares about (and he's finally admitted to himself he cares about them), like Watson and Mrs. Hudson, at risk. When Moriarty sets his "taint-Sherlock's-reputation" plan in motion, Sherlock realizes that the only logical conclusion to the plan is to make it seem like he killed himself out of shame; if Moriarty would just plain murder Sherlock, that would raise too much suspicions, and if he would let Sherlock live, eventually he would able to disprove Moriarty's false claims. After Sherlock figures out what Moriarty's ultimate plan is, he realizes he can use this opportunity to both get rid of Moriarty and make himself disappear from the public eye. (The WMG outlined above doesn’t take into consideration that Sherlock would want to fake his death in order to disappear permanently, which I think is strongly hinted in the episode.) He plays along with Moriarty’s plan to convince him he hasn’t figured it out, though in reality he’s not stupid enough to think a simple piece of computer code could let you through any security system.

When Sherlock sets up the meeting at the hospital roof, he originally intends to: 1) let Moriarty explain his plan, 2) then kill Moriarty, and 3) fake his suicide. Sherlock wants Moriarty to explain his plan, because he guesses Moriarty probably is gonna threaten his friends in order to make sure Sherlock does what he wants, so he needs to make sure his friends are safe before getting rid of Moriarty. His original plan is simply just to kill Moriarty, and then fake his suicide, then start a new life under a new identity. To the public, it would just seem like Sherlock the impostor murdered the actor who blew his cover, then killed himself out of guilt. This would allow Sherlock to get rid of his arch enemy and still walk away scot free. (That’s why he does the ”I’m at the side of angels, but I’m no angel myself” speech; an angel wouldn’t have planned on murdering Moriarty.) However, while he’s at the roof with Moriarty, he finally figures out what Moriarty’s ”final problem” is: stayin’ alive. To Moriarty, life is so boring that the kind of games he plays with Sherlock is the only thing that keeps him going. When Sherlock realizes this, he figures out that he can actually make Moriarty kill himself, if he can convince Moriarty it’s the only way to win the game. He manages to pull that off. (Some theories, like the WMG above, suggest that getting Moriarty to kill himself was part of Sherlock’s plan from the get-go, but I’d say that is taking Batman Gambit too far; even Sherlock couldn’t have predicted things that well.) Now, with Moriarty dead and knowing his friends are safe, Sherlock can fake his suicide.

The mechanics of how Sherlock fakes his death are not important, though it seems likely that Molly and the biker who runs down Watson are part of his plan. It also seems likely that Mycroft is involved. Presumably Sherlock contacts Mycroft at some point and offers him this deal: I will get rid of Moriarty for you, if you help me fake my death and set me up with a new identity. With the sort of power and influence Mycroft has, this would be easy to do. So, in the end Sherlock’s plan works just like he wanted to: Moriarty is dead, neither Moriarty’s men nor any other foe of Sherlock will threaten the lives of his friends anymore, and he is free of public scrutiny. Presumably he still plans to continue his detective work (how could he not?), but in another part of the country – maybe even another country altogether – where no one knows him, and under a different identity.

The reason Sherlock can't reveal the truth to Watson even after he's successfully pulled off the fake suicide is that he fears Watson will then come looking for him, which would both blow his cover and put Watson to risk again, if any of his enemies wants to get to Sherlock through Watson. He did tell the truth to Molly and (probably) Mycroft, but that's he because he needed them to fake his death, and because he doesn't think they will be in danger. Because of the way he's treated Molly in the past, Sherlock assumes no one will think she is close to him; this is kind of confirmed when Molly isn't among the friends of Sherlock that Moriarty threatens to kill. As for Mycroft, well, a man in in his position can take care of himself, so Sherlock isn't worried about him. Also, because of their estranged relationship, Mycroft isn't very likely to seek him out after his identity switch.

The Major's Sarcastic Confession about aliens in The Hound of Baskerville was true.
Aliens vs Sherlock. How cool would that be?

Sherlock was resurrected by Alduin.
Benedict Cumberbatch plays Sherlock Holmes. Benedict Cumberbatch will play Smaug in the upcoming adaptation of The Hobbit. Therefore, in addition to being a Time Lord (see below), Sherlock Holmes is a dragon and was resurrected through suitably draconic means. The logic is flawless!

In The Reichenbach Fall, the person ultimately engineering the kidnap of the children was their own father.
Think about it- there are many references to Hansel and Gretel and parallels drawn between them. In the fairy tale, the children are led into the woods by their own father, who is acting on the wishes of his new wife. He originally means to murder them outright, but changes his mind and simply abandons them. We know that Max and Claudette's father is an ambassador who is apparently innocently in America. There is no mention of their mother in any way- certainly not of her being contacted, so it's more than likely that she's dead. Father has his eye on potential wife #2. She won't "have him" because she's against the idea of inheriting two stepchildren. This guy had the power, money and means to consult Jim Moriarty (he's a consulting criminal, remember?) on the best way to kill his children and get away with it. Jim simply used the situation to ensure that Sherlock was implicated in the crime.

The "I Believe in Sherlock" movement will become an in-universe movement next series
Rule of Cool and it would be a treat to all the fans who went out of their way to show devotion to the show.

The body that fell of the roof was actually a Teselecta.
Much like the Doctor, Sherlock decided that he was getting too famous. Fortunately for him, the Doctor shows up (having just faked his own death) looking for a companion. Sherlock sees this as a perfect opportunity to disappear for a while and let everything die down. He ended up hinting to Molly that he might die because he knew that he was going to stage his own death very soon. So the Sherlock that Moriarty was talking to on the roof was actually a Teselecta with Sherlock inside. However during Sherlock's travels with the Doctors they encounter the Winchesters and take them in as additional companions. Sherlock ends up really missing John and convinces the Doctor to take John with them on their travels. Thus SuperWhoLock is born!
 * This Troper would like to inform you that her year has now been made thanks to that WMG.

It is somehow significant that .
If you were It just stuck out as unusual to me.

That Sherlock is alive will be revealed to John by his leaving a trail of clues.
Because that sounds like something Sherlock would do- he's been urging John for two seasons to improve his deductive faculties and to see rather than just observe. Once he was reassured that neither he nor John would be endangered by his reappearance, he'd be smart enough to leave enough inconsistencies and evidence to function as clues until John works it out. And then, predictably, not see a problem with this and wonder why John is so upset at him over it. The actually face-to-face reunion? The end of the first season 3 episode, not the beginning.

In Season 3, Jacob will try to prove Sherlock's innocence to the world.
Jacob Sowersby is one of the characters that are pretty much exclusive to the blogs. He is Sherlock's No. 1 fanboy, is quite obsessive about him and has some (harmless) stalker-ish tendencies. In this video, he shows off his huge collection of stuff related to Sherlock Holmes, including newspaper articles and all. If the "I believe in Sherlock Holmes" movement existed in the actual Sherlock-verse, Jacob would probably be the one to start it. It is possible that he (along with other fans) will go through his collection and point out why Sherlock can't have committed all of those crimes he has solved himself, as Moriarty wanted to make everyone believe.

The Reunion will take place in the lab at Barts.
It's the place where Sherlock and John first met and also the place where they had their last face-to-face conversation before the fall. It would only be fitting that it's where they meet again.

Moriarty is dead, but that won't stop him
Moriarty was able to blackmail people he wouldn't even know the identities of beforehand while in prison. This means he's got to have a network of accomplices, and maybe also sleeper computer programs set to do something at a specific time. He might well have plans in place for any number of activities in his name after his death.

John will track Sherlock down by his mobile phone.
John obviously knows Sherlock's phone was on him at the time he died, because he called him on it. So: phone goes missing. It takes the grief-stricken John a while to process how odd this is that even a mangled phone wasn't found on the body. [Edited to add: or that a phone was not found at all.] One day, out of grief and honest curiosity, he tracks down the phone by its internal GPS. He finds out it's in the building he's currently standing in. He calls it. And somewhere off to the side, hears it ringing... Sherlock will no doubt congratulate John (in his veiled-insult kind of way) on his deductive skills using his experience with the cab driver case to track him down. Seconds later, he'll probably get punched in the face.


 * Except it was implied that John saw Sherlock toss his phone away, hence why he stopped talking to him on his mobile and called out; "SHERLOCK!" Theory could still work though if no phone was found on the roof.
 * John called out to him because, just prior to throwing the phone back, Sherlock hung up on him. He was too far away to have effectively seen what Sherlock did with the phone, though he may have seen the (reasonably subtle) arm movement. That Sherlock made the effort to quite gently throw the phone behind him may also imply that he wanted it to be recovered by an accomplice (Molly?) at some point in the ensuing post-jump drama. It's unlikely that Sherlock uses his phone simply to text and call- he probably has important information on there that he wanted to keep.

Sherlock is a Timelord. Actually, everyone is a Time Lord
I'm sorry. Somebody had to say it.

Harry Watson will appear in Season 3
Played by Catherine Tate. Her sympathy about Dr Watson's insistance that "we're not a couple" will be evident, as she and another Doctor frequently had to assure people they weren't a couple either.

Sherlock has ADHD.
Primary inattentive type. He's prone to hyper-focusing, has problems with selective attention, and is habitually disorganized. He frequently throws tantrums (strong emotional outbursts that dissipate quickly) and likes to make noise (talking, playing his violin) when thinking. His drugs of choice (cocaine and nicotine) are both strong dopagenic stimulants. Nicotine in particular affects many of the same pathways as Adderall and is used by many people as a legal alternative to more strictly-controlled substances.

This puts Hounds of Baskerville in a rather more tragic context—John basically took away Sherlock's ADD meds, pushed him into accepting a case, and then got upset when the poor guy had problems focusing. Way to be a doctor, John.

Moriarty has read Arthur Conan Doyle Sherlock Holmes books.
Look at his glee when he quotes a line from the books or in Reichenbach Fall where he keeps on saying "Final Problem" there is no way these word would mean that much to him unless he knew about the books.

One of the OOC points about Sherlock's rooftop behaviour in Fall was showing agression.
We rarely see Sherlock physically strike out against someone, all agression towards people has been verbal or suggestively threatening. Yet Sherlock hauls Moriarty to the edge of the building... for what? They both know Sherlock wouldn't kill Moriarty, it wouldn't solve Sherlock's situation. Maybe Sherlock needed to make sure Moriarty didn't see something behind him, eg whatever Molly was setting up below.

In the world of Sherlock, the Sherlock Holmes books do exist
... but Sherlock Holmes of the books is called Sherringford Hope, the original name for the character proposed by Arthur Conan Doyle, and so the similarity goes unnoticed.

Moriarty had a fake Sherlock corpse, not an actor.
He left it near the children, taking it away just before the yard found them. The little girl didn't scream because Sherlock looked like her kidnapper, but because Sherlock looked like the dead guy in the corner, and dead people don't turn up to ask you questions without some serious shit going down. That body is also what Sherlock uses to fake his body when John came to look.TP

Season three will begin with John Watson reading a newspaper in his (not 221B) sitting room - turning to his wife Mary - and saying "Hmm...seems Sherlock Holmes is alive."
Because TPTB are evil, and know canon inside out. They've set us up for an emotional reunion - or a faint - so that's what we won't get.

And Moffat has already said “He and Holmes don’t always live together and I think that’s become a lazy way of doing Sherlock Holmes – they always live together. They didn’t actually and why would they? Nobody flat-shares forever, so there’s loads of details we can get in there.”

But I quite like the notion "Anthea" will turn out to be Mary.

Sherlock is not on cocaine during the series, but he has a history of it beforehand.
Because why, in "A Scandal in Belgravia", would John and Mycroft be so concerned over him starting to smoke again? The language used ("Can you be sure it's a danger night?") and the fact that John was prepared to let his girlfriend down in order to watch him seems to indicate that it is something more worrying than cigarettes.

Sherlock's father is Gregory House.
Sherlock's mother, already married with a child, had an affair with a gruff sarcastic American doctor which resulted in Sherlock. Sherlock probably figured out he was an illegitimate child at an early age, which created a rift between him and his parents. Mycroft became Sherlock's reluctant emotional support and mentor during their childhood, but the result was a sociopathic and cynical man. Like father, like son.
 * Ever hear of the short-lived series Fortysomething? In a way, House is indeed Sherlock's son!

Sherlock acted out of character in thanking the 'assassin' who saved his life. This is linked to I.O.U. and Moriarty's plot
The writers have hinted that Sherlock acted out of character during the final episode, and that this gives a clue as to his final actions. All through that episode, whilst Sherlock received various accolades, John had been on hand to remind him to say thank you, because Sherlock is notoriously bad at showing gratitude to anyone. Yet as soon as the assassin pulled Sherlock out of the way of the bus (after Sherlock had got out of Moriarty's taxi) Sherlock shook his hand and thanked him profusely (leading to the assassin's death, but there you are). This is because Sherlock had already worked out the code I.O.U. and knew that his friend's lives depended on him going along with all of Moriarty's plan. If Sherlock had died at that point, then he would not be able to save his friends. The code I.O.U. could be connected to their place in his life, but so far this troper has only been able to come up with I for Inspector (Lestrade). O could stand for 'One' (as in Moriarty saying he was going to get himself a 'live in one'), so that could be John, but if Inspector clearly stands for Inspector (as per my theory) then I don't think the other designations would be so vague.

Anthea is James Moriarty (Sr).
There are several points of notice about the character of Anthea that I find interesting. First is, obviously, the fact that her name is false. Second is that she feels no concern over John knowing this fact. Also, she finds it funny when John asks if she has any free time, sarcastically commenting that she has loads but implying that she in reality has next to none. We also always see her on her Blackberry, but never calling someone. This implies that, if she is in contact with someone, or more than one person, she has to retain anonymity. The most intriguing fact about Anthea that I have noticed is that she pretends not to have a good memory. This is shown when John says hello to her and she gives off the air of not remembering him, even though they met earlier the same day. Next is when Mycroft mentions stepping up their surveillance, and Anthea acts confused about who Mycroft is referring to. Now, how do I know both of these instances were an act? Because, during their very first meeting, John introduces himself to Anthea, and she specifically mentions that she already knows who he is. There’s nothing wrong with her memory, and especially not for people’s names and faces.

Now, why do I think Anthea might be James Moriarty Sr? False name, pretends a poor memory for remembering people (a special mention should be made that Mycroft of all people seems to accept her poor memory as a given, which as far as I’m concerned proves that Anthea is dangerous). There’s the fact that she is constantly on a phone, but never calls someone. This implies, as stated above, that either she or the party she contacts needs anonymity. It could also imply that she has trust issues, never revealing her voice over the phone to a face that she cannot see. Or it could imply that she simply very much does not want anyone to ever overhear her conversations and who she is communicating with. In all likelihood, it is a combination of these reasons. There’s also the fact that a sibling thought to be male but turning out to be female has already been foreshadowed. Even if Anthea herself turns out not to be James Moriarty Sr, it wouldn’t surprise me at all to learn that James was a female in this adaptation. Still, no matter what, Anthea is definitely more than she appears.

In the Sherlockverse, Sir Arthur Conan Doyle wrote stories about an actor named Benedict Cumberbatch.
Because it fits so neatly.
 * Adding to this for the sake of irony, he thought it was his greatest work, but it was overshadowed by the far more popular Professor Challenger books, as was the rest of his work.
 * Today, Steven Moffat and Mark Gatiss are preparing for the third series of George.

How Sherlock survived the Fall has something to do with tea.
This first came through as just being symbolic, but it's still worth suspecting that this could be a plot point; during Moriarty's heist in the beginning of The Reichenbach Fall, every single target shows someone with a cup of tea but no shot of them drinking it. (The banker might have just started to take a sip.) When Moriarty visits 221B, Sherlock makes tea. Sherlock, who wouldn't leave the house to buy milk or reach into his jacket pocket to answer his phone. He wouldn't make tea unless he had a reason. And when Moriarty arrives, he takes two sips while Sherlock simply rests his mouth on the cup. You can tell Moriarty did drink some tea when he taps his fingers on the arm of the chair, and the cup is a little less full.

Sherlock was the cab driver to the graveyard at the end of The Reichenbach Fall.
Would explain how on earth he knew John and Mrs Hudson were there, and just so happened to be there. And sort of even serve John right for not checking the cabbie, a lesson he should have learned by now.

On that note:

The murderous cabbie in A Study in Pink was the one driving the cab to the Brixton crime scene.
As Sherlock comments later, criminals like the cabbie are in it for appreciation and the spotlight. It's likely that he would want to see how the great Sherlock Holmes was taking in the crimes he'd committed. There are a couple of shots of Sherlock and John which seem reversed, because they're seen in the rear-vision mirror of the cab- that is, from the cabbie's point of view. He's watching them, and listening to the conversation they're having. Which means he was able to collect quite a lot of knowledge about John to tell Moriarty (or his cohorts) that night.

John already knows Sebastian Moran.
Listen very closely to the beginning of the first episode. Just as he wakes up from the Afghanistan dream, John screams something. It echoes, a lot, and is very hard to understand, but he calls out a name. "Sebastian!" Law of Conservation of Detail says that if we already have two separate characters named Sebastian, then a third person, with the same name, who was in the army at some point, is less likely than the one John knew and the one who works for Moriarty being the same person.

Sherlock wasn't faking his
Sherlock was genuinely trying to  because if you look closely at his face, it is wet, showing that he is crying, for no apparent reason other than fear of dying. So the  might have have been genuine. So how is Sherlock  I hear you ask? Someone else  without his foreknowledge!