Fringe/WMG

The Observers are outcasts in their society who want to find a way to fix the world of their time

 * The Observers managed to avoid becoming Sense Freak's like the rest of their society as shown in Letters of Transit and have used that to allow themselves to be able to travel back in time to observe events related to the pattern which could give them technology and knowledge of how the world was wrecked and how to fix it, provided that they don't interfere and change the future.

Theories regarding the Future of 2036 AD shown in the episode "Letters of Transit" go here:

 * "Letters of Transit" is the future of the original, Blue/Red Timeline, not the Amber Timeline:
 * Evidence: The existence of Henrietta "Etta" Bishop (Blue Olivia and Red Peter's child?)
 * Peter and Fauxlivia's child was a boy named Henry.
 * "Letters of Transit" depicted another the future of the Amber Timeline:
 * Evidence: If we consider Amber Olivia as essentially Blue Olivia now that Blue Olivia's memories have dominated her; also the survival of William Bell in amber begs the question of which timeline leads to "Letters of Transit."
 * Further Evidence: Etta can prevent herself from being "read" by the Observers (if the timeline wasn't reset, then maybe she has this ability because her father was Redverse Peter who appeared in the Amber Timeline, a man from "outside time" somewhat like the Observers themselves.)
 * If in the Amber Timeline the Observers can read Peter, the above presumption would be Jossed, but "Letters" could still have shown the Amber Timeline's future.
 * Etta's ability might come from Olivia recently being injected with Cortexiphan.
 * "Letters of Transit" depicts a possible future of a completely different timeline we haven't seen yet:
 * Evidence: William Bell is still alive and preserved in Amber.
 * That's not William Bell at all:
 * The ambered William Bell could be one of the Human-Shapeshifters.
 * Amber-Timeline William Bell traveled forward through time to the year 2015, where he got ambered with the rest of the original Fringe Team:
 * This might mean we are dealing with the future of the Amber Timeline, as William Bell's death (unexplained in that timeline) could have been just a disappearance due to Time Travel.
 * The original Observers like August, September, etc. were of a different, more benevolent (or at least, less aggressive) caste of future Post-Humans than the "neo-Observers" who were depicted as ruling a post-apocalyptic Earth in "Letters of Transit"
 * Evidence: In "The End of All Things," September told Peter that he was a member of a scientific observation team, and that September was a code name. Captain Windmark (Wenmoc?) and the other Observers in the year 2036 do not behave like detached scientists on a research mission. They take a much more active role by subjugating the human "natives." They also appear to enjoy parties and loose women. They also lack the distinctive odd cadence to their speech that the previous Observers displayed (though maybe this comes from living alongside modern-day humans for 20 years). Walter himself even says "They're not all bad. One of them, called September, tried to help us." Perhaps the "Scientific Team" represents a different political or cultural faction of future posthumans than the Observers who took over the world in 2015?
 * Resetting the Timeline from Blue to Amber resulted in the future shown in "Letters of Transit."
 * Resetting the Timeline from Amber to Blue resulted in the future shown in "Letters of Transit."
 * Resetting the Timeline from Amber to something else entirely (not Blue) resulted in the future shown in "Letters of Transit."
 * If the future shown in "Letters of Transit" is explored further in Season 5, the show will focus on the similarities between that future and the present of the Redverse:
 * Rationing. Environmental degradation. Coffee unavailable except as some kind of chewable substitute. A war with an extradimensional foe. Also, now that a particular piece of Walter's brain has been restored, I would not be surprised if 2036-Walter shows more and more signs of becoming like Walternate. The Fringe Division certainly seemed to see Walter as a new hope for the human race, possibly even a potential leader, like his Redverse counterpart, the Secretary of Defense and leader of Redverse Fringe Division.

The Observers are all anomalies in the timeline...

 * ...and September is Henry Bishop.

The 4th season (or possibly the mid-season break) will end the Amber-timeline and restore the Blueverse to its original state.

 * Leading to the world's most epic, "Hey, where ya been?"
 * Given that Peter needs to have a baby with Blue Olivia, this looks increasingly likely.

In the Amber-Timeline, as in the original timeline, Walternate was both aware of another universe and had sent shapeshifters over before our Walter.

 * The experiments that allowed Rebecca Kibner to recognize people from the alternate universe predated Walter's trip there to save//kidnap Peter. The episode implies Rebecca had seen shapeshifters in the 70's. We also have hints that Bell had already traveled to the alternate universe, and according to Walter, the shapeshifters were designed by Bell as part of his work for Walternate and the AU Department of Defense. We don't know which side crossed first, but the flashback in "Peter" definitely wasn't the first crossing, though our Walter believes it was.

The rest of the cortexiphan kids had their own series: Heroes
The Company is a Division of Massive Dynamic.

The Observers report to Uatu the Watcher.
An alien species of bald guys that simply watch and are not supposed to interfere... Of course Uatu is much bigger than your typical Observer so the Observers must be his Mini Mooks.

There will be a Redemption Equals Death moment for either Walternate or Fauxlivia

 * Likely in the series finale, one of them will make a Heroic Sacrifice to block the eventual destruction of one of the worlds.

By the end of the series, Olivia will become a full-on Reality Warper
The events of "Subject 13" and other episodes suggest she has this latent ability. It won't be long before she taps it.
 * So far the only powers she ever manifests are Telekinesis, pyrokinesis and greater control over universe crossing.

(cross posted from the Altered States WMG) The movie Altered States is the backstory of Fringe, with the names and dates changed to protect the innocent.

 * Walter Bishop --> Eddie Jessop
 * Nina Sharp --> Emily Bishop
 * William Bell --> Arthur Rosenberg

However, through the Literary Agent Hypothesis, the characters of Nina Sharp and Elizabeth, Walter's wife, were merged into a composite character, transfering her affections from William Bell/Arthur Rosenberg to Walter Bishop/Eddie Jessop. Bishop/Jessop harvested cortexiphan from his own spinal fluid after his encounter with the primordial consciousness in the movie. Arthur/Bell went on to found Massive Dynamic with Emily/Nina, but Bishop/Jessop was made permanently insane by the experiment and was confined to St. Claire's.

Sam Weiss is Seamus Wiles, the author of the book "The First People," and a member of that race.

 * He's older and taller than he appears, and their names are similar.
 * Not just similar, Seamus Wiles is an anagram of Samuel Weiss.
 * Actually,
 * Actually,

The alternate universe in fringe...
Is the main universe of OUR alternate universe's Fringe. Everything that happens in the alternate universe is the stuff they see, while the stuff that happens in our Fringe's universe is the stuff they don't.

Walternate wants to steal the rest of the machine from our side
This explains everything (plot-relevant) he's done this season so far: This way he can get his Doomsday Device up and running, and then (should the crossing over research pan out)swoop in and grab both Peter and the device, then activate it.
 * Replacing Olivia with Fauxlivia, then using her to set both Peter and Walter on constructing the machine.
 * Brainwashing Olivia and then using her as research into crossing over safely.
 * Confirmed as part of his plan at the very least.

Newton's Just Hiding.
He's cheated death before (recovery from decapitation anybody?). Also, I wouldn't be surprised if Newton would be around to stare balefully at Fauxlivia as she is exposed, Magnificent Bastard that he is.

Agent Dunham is going to quit the FBI and start working with Massive Dynamic.
Agent Dunham gets kidnapped, and the first thing the Feds do is put her under arrest and assign a convicted felon with a grudge against her to be her supervisor and be generally obstructive. After a few more episodes of this, she's going to decide she's had enough and take up Nina Sharp's offer.

Agent Dunham killed Walter's lab assistant
17 years ago, a lab assistant was killed in a fire in Walter's lab. A little more than 17 years ago (give or take a few years, maybe) Olivia was struggling with her drug-induced mental powers, and she was starting fires with her mind. Coincidence? quite possibly, but can you imagine?

Astrid is in love with Olivia
She's willing to take care of Walter because if Walter goes back to St. Claire's, she won't be involved with the Fringe Division anymore, and won't be able to be near Olivia. Seeing Olivia in her underwear when she goes into the tank now and then helps too.
 * Well, her actress, Jasika Nicole, is in fact lesbian...
 * She either told Walter or he picked up on it on his own and then incorporated it into his story in "Brown Betty." See the Les Yay entry on the main page.
 * Season 4 will be all about SS Wastrid.

Massive Dynamic = Umbrella
And it's only a matter of time before they release the T-Virus.

Massive Dynamic = Crey Industries
And Nina Sharp is really Countess Crey in disguise. Just wait for the Revenants to start showing up.

Peter is a clone of Walter
The episode "The Same Old Story" gave many possible hints to this. Walter left Peter's life when Peter was 13 and yet seems to know so much about him. He says 80% of Caucasians are born with blue eyes, but Peter's were green. He says Peter was always patient. Peter counters that by saying Walter doesn't know him well enough to make that statement, but Walter tells him there is "much he doesn't know." He tells Peter he always had a way with women; seeing he hasn't seen Peter since he was 13, there was no way he should have known that. Walter says that because he had a way with women. When discussing the 80-year-old baby, he said it was identical to the experiments he conducted 30 years ago. Peter is 30. Then there is that cryptic conversation at the end where he assumes Olivia knows about Peter because she read through his files and knows his medical history. When Olivia says she only knows his birthday and nothing else, Walter keeps his mouth shut and shrugs it off.
 * Furthermore, Walter repeatedly mistakes things about himself (things that happened in childhood, his favorite things, etc) for things about his son.
 * Coffee Yogurt anyone?
 * Or Walter is a timetraveler and he semi-consciously knows stuff about Peter. Furthermore his time-space destination is the fateful day/night when the laboratory is burned, but thanks to his intervention the fire is started and secondly the Walter from the future was imprisoned to the penitentiary, the old Walter is somehow dead...
 * Combination: Walter is a time traveling version of Peter. Or Peter is a version of Walter from the alternate world.
 * Something: Walter is a Time Lord and Peter is a future regeneration. Or the other way around.

Fringe is in the same universe as Star Trek
Some of Walter's research led (will lead?) to the Eugenics Wars.
 * The Eugenics Wars took place in the mid-to-late 90s in the Trek 'verse.
 * Fringe takes place in Abrams's Star Trek franchise.
 * And as far as Abrams is concerned, all his works are in the same universe. Note the recurring Slusho.
 * And a reference to the doomed Oceanic Flight 815 in the pilot episode.
 * SO is Fringe before or after Cloverfield?
 * In the latest episode, they beamed someone from Germany to Baltimore.
 * One of their sources in 1x19 (played by Clint Howard) is a demented Trekkie. That would seem to Joss it, but maybe he just knows more than he should.
 * Fringe takes place in a parallel universe to Star Trek. Walter's research in that universe led to the Eugenics Wars.
 * Fringe takes place in a parallel universe to Star Trek. Walter's research in that universe led to the Eugenics Wars.

Walter knew the Doctor and/or Captain Jack
You know that's the only explanation for the hand-in-a-jar.
 * But he established that the hand was not a friend's, so that must mean... no. We have enough Masters already.
 * Actually his response when asked if the hand was a friend's he said, "I certainly hope not."
 * Walter hid some of his old classified stuff at "Harkness" Library...

Fringe takes place in an Alternate Universe
An alternate universe where the laws of physics are slightly different. For example, you could probably build a perpetual-motion machine there if you just tried hard enough and spewed enough technobabble.
 * This is true of almost every science fiction universe. But the laws of physics in the Fringe Verse are more different than many; a fetus can grow to adulthood without any mass to feed on, and a hallucinogen can cause death wounds.
 * It has recently been established that there is an alternate universe in conflict with the main one. There Can Be Only One.
 * It's possible that the reason the Fringe universe allows such bizarre science is because its physical laws have been altered by contact with matter from the other universe, where those laws are clearly different, given their advanced use of impossible technologies. This is the basic premise of Isaac Asimov's The Gods Themselves, and Fringe has already referenced classic sci-fi on several occasions.
 * That aspect has been confirmed. The Pattern is the laws of physics "breaking down" to do humanity's actions to the universe.

Walter is behind everything.

 * Aware of his imminent commitment, he arranged for his research to fall into outside hands. Why? Because they'd need to get him out of the asylum to deal with any resulting situations. Not the most grandiose of devious plots, but hey, he's insane.
 * Interestingly enough we have just found out that Walter wrote the manifesto that the "bad guys" (they haven't given them an official name yet)follow was written by Bishop, though he doesn't seem to remember doing it.
 * He also preformed the experiments on Olivia when she was a child, and he also built the teleporter among other things. He also knows that he wrote the manifesto and ran the experiments and hasn't told anyone about it.
 * Additionally, Water could have realized that The World Is Not Ready for his technology, and started the fire in his lab on purpose in an attempt to kill William Bell, followed by him pleading insanity, leading to his institutionalization. However, since Bell survived the fire, he was able to form Massive Dynamics, leading to the Pattern.

The Observer is:

 * An Agent of The Pattern
 * He rescued the Bishops because he knew that Walter's experiments would be put to use in The Pattern. Now he's watching the results of Pattern experiments to see how they go.
 * An Opponent of The Pattern
 * He works for a rival group who wants to stop whatever The Pattern is planning. His role is to gather information about the experiments and report them to his superiors so that they can figure out how to thwart what's happening.
 * Another G-Man
 * They show up at odd events and don't really fit in, yet they go unnoticed by ordinary people until they make themselves known. Their vocal inflections show that they are not normal. Neither can get hurt (yet), and they can move easily through time and space.
 * While rewatching the first season in preparation for the second, This Troper had an idea at the end of "Inner Child": What if The Observer is the future of that kid, who traveled back in time for some reason? At the end of the episode, they share a strange moment...
 * What if the Observers are the surviours of what killed off the First People? Who now hang around to make sure that history doesn't repeat itself.
 * Jossed, the Observer is a part of a science expedition from the future

Psychokinesis and Dark Matter will be the "fringe sciences" most significant to the plot.

 * In the intro with all the terms flying around, "psychokinesis" shows up twice. So does "dark matter." Maybe they'll both play a significant role, or maybe the creators couldn't think of any more fringe sciences.
 * It should be noted that Olivia has just demonstrated psychokinesis. And alternate realities could be the cause of dark matter phenomena.

Fringe and Lost take place in the same universe.
And Massive Dynamic = The Dharma Initiative.
 * And Phillip Broyles = Matthew Abaddon?
 * Walter Bishop was a member of the DHARMA Initiative, which would explain a lot.
 * And as far as Abrams is concerned, all his works are in the same universe. Note the recurring Slusho.

Astrid Farnsworth has relatives in New York.
Namely, a young man named Phillip J. Fry.
 * Well, the First Phillip J. Fry's nephew and namesake was probably born around 2009. That Phillip J. Fry will become the First Man on Mars and eventually marry Astrid's unborn daughter. One of their children will choose to go by Astrid's maiden name rather than Phillip's and be the direct ancestor of Hubert Farnsworth.

Massive Dynamics = Global Dyamics
Both have insane ubertech, and the names are too close not to be mentioned. Additionally, Eureka is set at about the present day, but Fringe is a few minutes into the future- Nina Sharp and Eva Thorne are the same person a few years, some makeup, and a cover story apart.

Fringe is in the same universe as Narbonic
We see mad science, teleporters that sorta work, crazy genetic experiments that get out of hand, cyborgs, and the like. One of the villains is named David; maybe he's a Dave that was kicked out of the conspiracy (which would explain the teleporter).

Fringe is in the same universe as The X-Files
The Pattern and associated phenomena and organizations play a parallel role to the Syndicate, to prepare for the alien invasion in 2012. Certain people, such as Walter Bishop and the kid from The Equation, are being telepathically fed the information required to create the technologies involved in The Pattern by the aliens.
 * Confirmed (sort of) in the season 2 premiere; there's reference to the "X-designation," which used to handle this sort of work before the Fringe division was formed.
 * Then again, it's also somewhat Jossed in that same episode, since the X-Files is shown on a television in the opening scene, proving that it's a work of fiction in the Fringe-verse, unless of course this is some kind of odd case of in-universe Truth in Television.
 * In the first episode, we see Broyles meeting with Nina and others, and Nina mentions how the "previous team" was a disappointment. I can see Mulder and Scully being seen as a "disappointment" for some, if they failed to accomplish what this group wanted them to.

The ZFT was written by Walter's equivalent from the alternate universe
The ending to "Ability" suggests that it was written on his typewriter, but that he doesn't remember writing it, plus the whole "Science Is Bad and will kill us all" message doesn't sound like him. It was written by his evil double who has an opposing agenda but, In Spite of a Nail, the same typewriter.
 * Which could mean that Olivia's universe is the other universe referred to by the manuscript...
 * in Over There: Part 1.
 * Sort of. It's a book called ZFT, but it's not the same book as ZFT in the main Fringe-verse. Recall that ZFT-Prime describes the conflict between parallel universes in the multiverse. So they're definitely not the same book.

William Bell and Walter Bishop are the same person.
Strange isn't it that Bell and Bishop were close associates in the old days, yet we've never seen Mr. Bell in person, not even a photograph? In fact, Nina Sharp appears to be the only person who has interacted with Mr. Bell recently. Plus: W.B. and W.B.
 * Jossed in the season 1 finale.

The teleporter turned Mr. Jones into Man-Bat.
He will then kill Walter, Peter will swear revenge and use the Tank and lots of drugs to gain a life time of experience and kick ass.
 * Jossed. It just really messed up his face and forced him to wear bandages to cover his decaying flesh.

William Bell and Walter Bishop are Peter's parents.
Through the wonders of science and a donated female egg, Peter has two daddies. It was either a gay fling or they wanted to created the perfect man and they didn't trust any woman's genes except for Olive's and she wasn't born yet. Fringe... because they did Mpreg. Now let's go there.

Massive Dynamic is not corrupt, and in fact is trying to save the world.
Because no one would see it coming.
 * Given how the FBI acts in this 'verse, it's not that far-fetched.
 * Surprisingly confirmed (though they still do some pretty messed up stuff).

The Observer is the key to everything
The Observer is from the other world, sent to this world to evaluate it for invasion. After saving Walter's life there was an exchange of information, probably mentally. This leads Walter to write the manifesto and team up with William Bell to start preparing for the invasion. The experiments made him go insane and William went on to found Massive Dynamics as a way to prepare the tools needed to stop the invasion.

At the same time this exchange of information made the Observer question his mission and he goes rogue. He's now trying to keep his own people from invading, sending the probes back before they can call 'home' and watching what is going on.

His people know he's gone rouge, and have recruited others to help with preparing the invasion, including David Robert Jones.

The child Observer is from Walter's world, and proof of the worlds getting closer.

The Peter in the series is the Peter from the other world
So Walter always talks about things from Peter's childhood, but Peter doesn't remember them. Furthermore, the most recent episode shows Walter  If that happened, then perhaps Walter went to the other world in the 1980s, took Peter, and then raised him in this world. This would also explain why he got involved in all of this in the first place: he wanted to get Peter.

In the other world, everything is different by one coin flip.

 * Well, that seems to be how Walter explained it in a scenario of whether you choose to go to work or stay home.
 * Additionally, explain that the other universe is the way it is due to people making different choices.

Nina Sharp lost her arm as a result of a world-breaching experiment.
The season finale showed us
 * Somewhat Jossed. Supplementary material says she was infected with cancer and had to have her arm amputated.

The Big Bad will be Alternate Walter
The season finale has the strong implication that. We also know that the alternate universe seems to be dealing with some sort of unspecified chaos, and that our Walter invented a device with the specific intention of preventing someone coming through from the alternate universe. Given the lengths Walter has gone to.
 * The Walter we saw when he went back to the asylum was Other!Walter, who had been terrorizing him during the entirety of his previous stay there.
 * Other!Walter could also have started the fire in the lab, killing the young lab assistant.

The Alternate Universe is Pete's World
. Albiet, Pete's World some time before Cybus Industries comes about. When it does, we will discover that the final showdown is between Massive Dynamic and Cybus Industries.
 * I know this isn't the place for Fanfic Recs, but since this fic was clearly written by someone who read the above WMG, I felt it was appropriate to put here.

Olivia's alternate universe counterpart is a man.
Olivia spent the pilot desperately trying to save her horribly injured, helpless romantic partner, and she's by far the most physically violent character on the show. She's also had telepathic contact with two different men, which led to her confusing her thoughts with theirs. We've even seen her make out with a female stripper, as part of the same telepathic link. So the show is constantly using Olivia as a "male" character, and the next step is to see the actual male version of Olivia. Obviously the other universe has an Oliver Dunham, born at exactly the same time as Olivia and with the same genetic makeup as her, except for having a Y chromosome where she has an X.
 * in Over There: Part 1.

The Observer is an extradimensional being, a human from an evolutionarily accelerated world.
The young observer child is not the only such being. The G-Man in that episode reported that they had found "another" one, with the implication that similar children had been found elsewhere. The child and others like him are mutant humans with genetic traits that future apocalyptic events will select for in Darwinian fashion. Such children will inherit the world and one day create an Observer civilization in this universe. However, in another universe, this has already happened. And the Observers from that accelerated universe are invading or preparing to invade ours.
 * I thought this was Jossed is Seasons 2 and 3, but now, with the latest Season 4 episode, "Letters of Transit," this theory might actually still be valid, at least in that timeline, if not others. So the Observers are actually from one (or more?) possible futures, not just an evolutionarily accelerated parallel world (though that's basically a minor point). But they are planning to invade, or at some point decide to stop observing and take over because their own Future Earth can no longer support life. It's still possible that the mysterious Child from Season 1 and others like him are the Observers' direct ancestors.

Father is involved in this somehow
Maybe he's working with the observer or Sanford Harris. For whatever reason, he's trying to keep an eye on Olivia, or most likely, Peter.

The Observers are a dimensional regulatory commission and they are pissed at Walter.
Positing that there are multiple Observers, They are a group of beings that exist outside of the alternate universes as we perceive them, and one of their duties is to make sure dimensional travel does not happen, as the reason they exist outside of the universes as we perceive them is that something... unfortunate occurred. The Observer assisting Walter has gone rogue.

The shapeshifters are a type of Terminator
They have mercury in their blood for one...

The Observer "distributes" the various power-causing technology around the country
They were locked up in some restricted area because of their dangerousness. The Observer found them, released them, and gave them out to various people, hoping they will be used in the upcoming arrival of the big shapeshifter army

Olivia is a relative of Jeff Dunham
They share last names. Then again, one of the producers of Heroes has the last name of Nakamura.

Peter switched universes with William Bell
It seems clear that Peter got sent from the other universe somehow, even though that's not normally possible, and that William Bell got sent over there somehow, even though that's not normally possible, and now William Bell can't come back. So William Bell, to help Walter Bishop get his dead son back, switched universes with alternate-universe Peter via some special "exchange program" sort of rule.

The letters that Olivia tried to put together in Dream Logic weren't meant to spell "You're gonna be fine"

 * They were meant to spell...
 * "You been on a fringe". Which is... y'know.. true. She's in pretty much all the episodes.

Charlie Francis is coming back
In the episode with the Combusto-twins, it was established that the alternate universe held an alternate Charlie Francis. Just because the one from this universe died does not mean that his actor can hit the bricks. I foresee Charlie having quite a bit to do with the upcoming arc, much to the surprise of Dunham and the rest. Assumed from Peter's being kidnapped from the alternate world.

Tyler is a young Kira
They look similar, and the mind control could have been some variation of a Death Note, given that he used it to kill people.

On a related note, Christine Hollis is Misa.
Kinda goth girl who's got extra-dimensional beings crushing on and  for absolutely no reason? Check.

Fringe takes place in the same universe as Trauma Center
Tell me that the thing in 'In Which We Meet Mr. Jones' isn't a G.U.I.L.T. Expy.

Fringe takes place in the universe of the League of Extraordinary Gentlemen, wherein every fictional story and character exist and intermingle with others.
This allows Massive Dynamic, your average 'sticky-fingers' corporation who can't keep its hands out of anything, to have connections with the Dollhouse, the Company (Heroes), the School (Maximum Ride), AND the Centre (The Pretender), and any other coorporation that focuses on sciences beyond normals means and that might posibly be used in a war with The Other Side.
 * Jumping off of that, in the League's universe, the Fringe Science division was created in the wake of Mulder and Scully's quasi-departure from the F.B.I. between The Truth and I Want to Believe. When they were active agents, Mulder and Scully used as reference materials a large case file of past strange and unusual cases (marked, of course, with an X) compiled in the 1950s by a television producer with an interest in the bizarre world around him, and who had the file sent to the Bureau upon his death. That producer's name...was Rod Serling. DooDOODoodoo DooDOODoodoo...

Astrid is the child of Walter's dead lab assistant.
This explains why she's willing to play babysitter to a whacko: she's looking for the perfect chance to kill him because "he went too far" or the like. She's gone out of her way to get him out of trouble because she wants to be the one who kills him.

Astrid is the secret love child of Nina Sharp and Phillip Broyles.
Sharp and Broyles had something romantic going on. Astrid is the product of this something and was adopted as an infant by who she now thinks are her parents.
 * Sadly, sadly Jossed. We see Astrid's father later on in the series.

Mad Science is part of the Bishop bloodline
The Bishop Revival reveals that Walter's father Robert was involved in the same sorts of experiments Walter did. Peter will eventually grow more erratic and follow in the footsteps of his ancestors.

The two universes are going to intersect completely on 5/20/10
Why else would Walter and William Bell try so hard to commit that series of numbers to memory?
 * It's the date that part II of the Season Finale will air, so...
 * Possibly Jossed, as that episode has come and gone, and no total intersection.

The virus from 2x13, "What Lies Below", is actually the Sickness from Lost.

 * Both of them cause people to go sorta-crazy--or more accurately, to act as though under someone else's instructions--while somehow remaining in posession of their mental faculties. And the fact the virus was cured by ash can't be coincidence.

The other universe is the Star Trek universe.

 * The biggest disconnect between reality and the backstory of Star Trek humans is that they were capable of advanced genetic engineering in the 1970's in order to have Khan running around in the 1990s. Obviously, they were decades more advanced than we are- say 30 years. Then, it has been established that the West was experiencing widespread chaos throughout the first half of the 21st Century due to the Eugenics Wars and other conflicts- conflicts such as a plague or revolt forcing half of a major city to be quarantined. Had the Observer not disrupted the timeline, then the universe would have continued as normal. Why is Peter so important? Well, he grows up normally- he gets married, and has a daughter. Later on, this daughter gets married herself and gives birth to his first grandchild. A boy named Zefram Cochrane.
 * And William Bell is the ancestor of Amanda Grayson, and therefore of Mr. Spock.
 * If the Alternative Universe is the Star Trek timeline then would that make the main (Blue) verse the Mirror Universe timeline?

There is absolutely no way to stop the destruction of one of the two colliding universes.
It's one or the other, and ultimately the alternate universe will lose. Walternate will send Peter back only seconds before the end to save him, leaving him as one of the only known survivors... until it is later revealed in the next season that others have also survived, likely seeking revenge.
 * Nope.

Alternate-Olivia will Become The Mask and later help Walter and Peter get the 'real' Olivia back.
She will also most likely die in the attempt.

Alt!Liv was sent by Walternate to make Peter switch sides
Alt!Liv told him about Peter and Olivia's relationship and her orders are to use her influence to get him to come back and destroy them.
 * If not full on convert him, at least manipulate him into helping without him realizing it.

Alt!Charlie is going to make a Heel Face Turn
Because the writers know we need Charlie back.
 * It'd be pretty simple to do, really. Reveal that Alt!Charlie is plagued by the death of his wife (maybe he somehow spread the arachnids to her or something and she didn't make it). He learns that his wife is still alive in the other universe, and incidentally has tragically lost her husband in a bridge-related accident. He decides that he's willing to leave his own universe to be with his wife again, and Walter (who, in the other universe, was too busy with his Son-powered Universe-murdering machine to cure Charlie) fixes up his nasty case of arachnids with about as much effort as it takes to eat a licorice twist.

This is leading up to the creation of a spin-off series about the adventures of the Alternate, military-run Fringe Team
Because it means we get more Charlie and a cheerfully nonchalant version of Olivia.
 * The writers have said that Season 3 is going to be half 'This Side' and half 'The Other Side', meaning HALF of Season 3 is going to be with the alternate, military Fringe Division.

Season 3 Episode 1 is going to consist of Olivia gaining/regaining the use of a ton of powers, busting out of the cell she's in, and escaping the alternate universe on her own
Well, Bishop and Bell keep saying that she was their best subject/creation. We've seen video evidence that she can light fires when she's afraid, we know that her ability to see Alt!Objects kicked back in when she was afraid, and she turned the light board off when she was afraid. Considering that now she's in solitary confinement, I'd say the chances of her Take a Level In Badass are fairly high.

In the Alternate Universe, George W. Bush was killed in office and replaced by Dick Cheney in in 9/11.
The increased militarization and regimentation in the alternate universe is partly a response to this. Evidence: we know the White House was damaged or destroyed on 9/11/2001 instead of the Twin Towers. Because it means we get more Charlie and a cheerfully nonchalant version of Olivia.
 * well the increased militarization could just be the result of the fabric of reality breaking down for the last 2 decades.

Alt!Liv was never treated with Cortexiphan as a child.
Peter says she isn't haunted like his Olivia. And nobody knows who Andrew Jackson is, so presumably there is no town called "Jacksonville." Compare Alt!Liv's easy going, relaxed attitude to our troubled, straight-laced agent. It's a world of difference.
 * Confirmed later in S3. After the Olivias return to their respective universes, Walternate.

Alt!Nina will be a bum or a mental patient

 * Or alternatively... she will be the victim of one of Walternate's experiments.

The Superweapon Walternate is building is of alien origin

 * Made pretty clear in Season 3, Episode 2. It is mentioned that the technology thats part of the Superweapon is quite ancient. The appearance of the devices themselves have a Sufficiently Advanced Alien look to them, their segmented appearance and odd, bronze tinted coloration resembling nothing we saw in either universe. To top it off, they have odd runes on them that just scream alien. Further supported by Walter's speculation that the Cortexiphan-fuelled abilities were common throughout humanity until their disappearance. At the point, it simply came off like Walter's usual crazed speculations but what if it was Foreshadowing?
 * Not to mention an alien entity did appear in Earthling.
 * Jossed it was really built by
 * It was built by the Ancients. C'mon, leaving a piece of universe-destroying technology around is JUST their sort of thing. (As well as the detail in spoiler text above).
 * Jossed, the superweapon from the First People was built by Walter and sent back in time.

The series finale will reveal the point where the two universes split.
Because it just seems like an obvious place to end the story. The superweapon will be fired, causing the universe to split in two, and its parts will be scattered.

Sam Weiss is the Real Big Bad
Everything else is just him manipulating events behind the scenes to his advantage.

The deceased Alt!Bell had a goatee!
Considering who was cast as William Bell, it just isn't possible to be any other way.

The Peter Doomsday machine was invented by Rambaldi.
Ancient tech, a strange and potentially apocalyptic machine powered by one chosen man, pieces that need to be found? It's got to be Rambaldi.
 * It also explains why Arvin Sloane planted a spy within Fringe division (Gene the Cow.)

Walter isn't actually to blame for the breakdown of the Alternate Universe.
We know that the observers and inhabitants of the Alternate Universe have repeatedly traveled to our universe without consequences nearly as severe. Sure sci-fi science is possible now, but we've experienced no 'black holes' that would warent the quarantine procedure. I realize Hollywood science is deliberately in play, but I just don't buy that one trip, granted a hasty trip using a machine that probably barely worked, could cause more damage than multiple and continuing trips. I think there are two good guesses as to what's really going on. 1: Walternate has lied or exaggerated about the severity of the dangers his universe faces, in order to gain the power he needs to pull off the revenge he has planned. Note that Fringe Division reacted to our Cortexifan heros entering their universe by almost quarantining it right then and there, only stopping because it stabilized. In the next season, we see that the theatre gets ambered anyway, probably under orders from Walternate, who wanted to keep Olivia over there. Who's to say that most of the other 'events' that have resulted in quarantine wouldn't have stabilized/not created a 'black hole'. All Walternate would have had to've done to convince their government to start the quarantine procedures is create one or two disasters and then lie about it. I mean he's a mad scientist, come on. Because of the scope of these tragedies, the government would do whatever would prevent more from happening, sealing off all situations which might create instabilities, and giving Walternate goverment power because he has 'prevented' any more disasters from occurring. 2:There are other universes, one of which is purposely causing the disasters which have been observed in the alternate universe we know of. Who said that there can only be one other universe? If they are using the quantum possibilities explanation, then there's no way there are only two. Look at the differences between them. The divergence point has to be somewhere after or just before the American Revolution. There are far too many similarities between the two for me to accept that they've always been two separate, unconnected universes. Given how different they are, if they had separate histories going back to ancient times, the Roman Empire might not have fallen, or China could have colonized North America, or fish people could have become the dominant species of the planet, or any of a number of things. Where do the Observers come from? They can travel between universes without apparent problems, but don't seem to regard either that we've seen as home. It just makes sense for there to be more universes........within the acceptable breaks from reality we already accept in this show.
 * The reason Walters single crossing did more damage then all of the alternate 'verse's crossing is because of the way they cross, Walter's device basically ripped a giant hole in the fabric of both universes, and while their world is having the worst effects, it's already confirmed that ours was also somewhat effected. After that a way was discovered to cross that didn't further damage the realities, but it's extremely dangerous, and has massive, cumulative side effects. which is why they developed the shapeshifters, cause they can use that means without the risks. remember, the first time Walter crossed he went there and back with no personal side effects, but when Walternate came over using the newer version he needed to be put in a hyberbaric chamber and load with medicine to recover.
 * Actually, it ends up being  fault.

The "Observers" are really a remnant of the "First Race" that

 * It just makes sense, it would explain why they are not "quite" human, there greater knowledge, advanced tech, etc...
 * Or they're like the Overlords.
 * Or they're G-men.

The "First People" will turn out to be a load of crap.
Because it's just too ridiculous, even by Fringe standards.
 * Well, there's a reason why the show's tagline is beyond the impossible.
 * Called it.

There was a third, "Original" universe, and the two we see in the show are the result of a disaster that split it
Unknown to either side is the fact that because they are fragments of the same battered "original" universe, their fates are tied together. If one goes, they both go, so Walternate's "only one can survive" mentality is ultimately the biggest threat to existence in the show. The only way they can survive is by merging back together to reform the original universe they split off from, otherwise it will all collapse. Moreover, because Olivia is the only person who can cross over naturally (among other abilities), she's the only one who can do anything to get the ball rolling. Her and Bolivia will have to make peace and come back into alignment as the "real" Olivia Dunham. Walternate will be the last big hold-out, and decide that the destruction of existence is better than the two worlds coming together, pushing him over the Moral Event Horizon and into truly insane villainy.

Walternate is to blame for the breakdown of the alternate universe
A variation of a WMG above. Walter and Bell didn't create much damage, and that the quarantine events are all a result of Walternate's efforts to get Peter back. Each quarantine event occurred when Walternate sent a shapeshifter or something else over, or after the magic typewriter's effects built up. This is one reason why Walternate is so eager to get cortexifan - as he puts it, his method of crossing over has "drawbacks."

The point of divergence for the two universes was when The First People activated the machine
Walternate wants it to destroy the other universe, but the mention of its powers of "creation and destruction" suggests it could be used for the opposite. Of course this would take the In Spite of a Nail issues to extremes.

Alternate-verse Gene...
Is obviously the Cow Behind The Man and is secretly using Walternate as an Unwitting Pawn!

The Rogue from "The Arrival" was an agent of the parallel universe, probably a shapeshifter
Access to ultratech, an unusual interest in Peter and knowledge of the Bishop Family Tree.

Peter knocked up alternate!Olivia
This would explain why the observer said it must be difficult for him to be a father before he shot him.
 * Or else he was simply musing about Walter's choice, and the thing that 'unites' is not their baby but rather something caused by shooting his gun-thing at Peter. How else do you explain Olivia's lack of tattoo and the backwards landscape?
 * Original WMG was by S03E13 "Immortality."

The Observers are sons of Chronos.
Or any other time god/goddess you like; for my purposes, it's Chronos. Think about it. They're present at major events in history, they're supposed to observe but not get involved... because the gods learned a long time ago that interfering can cause wars (which has transmuted into altering the timeline is bad). And they have a dulled sense of taste because they're used to ambrosia.

We will see Christina again.
("August") We have to. August died so she wouldn't have to, and September said he'd made her important (The Power of Love). She has to come back, in some capacity.

We will see a Tyler at some point.
("Of Human Action") We have to, or there wouldn't have been mention of the fact there's more than one of them.

Fringe exists in the same universe as both House and Law & Order: Special Victims Unit.
The number of sick people in House and the number of sickos in L&O:SVU are part of The Pattern, except no one at Fringe has seen it because that's not precisely "paranormal," it's just odd.

Peter will not survive the series.

 * One, because having the power to destroy universes can never end well. Even if the crisis is averted, those in power are hardly going to let the bringer of the Apocalypse go off on his merry way. Two, because the Universe(s) hate Olivia Dunham. As much as I like him, I think the poor guy is doomed...

Season 3 will end with an in-universe reboot.
Peter will, but the result won't simply be the destruction of the main universe, it'll reboot it. Like was said, the machine is. Rebooting the main universe will allow the writers to bring back dead characters in Season 4  and show what history would have been like if Walter had. The only two people to remember what happened in the 'old' universe will be Olivia, due to her reality-hopping abilities, and Peter. Olivia and Peter coming to remember each other, and realizing they *do* love each other after all, will set up the Big Bad of Season 4:.

The original and unsuccessful Fringe team...
...that Broyles mentioned in episode 2, consisted of John Scott, Hicks and that were hedgehog guy (whose name escapes me). Broyles and Sharp know all this and are keeping this from Olivia for some reason.
 * This is a pretty good guess, based on the episode "The Transformation."

The kid from Inner Child...
...is a young Observer. He's bald, psychic, doesn't say much ,just a little creepy and actually noticed the adult Observer watching him. He definitely fits the bill.

Broyles is an Observer.

 * Doesn't he look and dress exactly like a black Observer? We haven't seen him eat much, either.
 * high!Peter seems to think so.

Each universe has its own plot-significant hat.
The alt-verse, despite its advanced medical technologies, is especially vulnerable to epidemics/pandemics: smallpox, avian flu, the extinction of sheep, blights that have made coffee and avocados extremely rare. Some of the more recent events may be due to that universe's fringe events triggered by Walter's actions, but the last human case of smallpox in our own world was in 1979. Plus, even with all the routine catastrophes of the alt-verse, the complete modern extinction of an animal as widely distributed and economically important as sheep suggests a special weakness.

The main-verse seems like the "normal" world, but the residents are more vulnerable to infiltration by impostors. Peter has tried to rationalize it away, but. Shapeshifter infiltration is even worse: not only do they need to keep up a perfect con, sometimes for years, sometimes embedded in a human family, their physiology is so non-human that it should give them away far more frequently. At the very least, all that mercury should make them weigh nearly twice what their unfortunate target did. People in the main-verse, however, are simply less able to pick up on things being "off" with someone, and so the alt-verse has gotten away with replacing an unknown number of people with spies.

Peter will get our Olivia pregnant.
We know now that and that every person exists at some point in both universes. Take the example of - even though they're dead, they still existed. And as we can either assume that  or, more likely considering Walternate's plans for, Peter will get our Olivia pregnant. Bear in mind that despite differences in the person themself between the universes, their DNA remains constant, so if
 * Err... no they don't. There are people who exist in one universe who don't exist in the other. Case in point, "6B". The old woman was childless in our universe but apparently had kids in the other one. The chances of Peter and Olivia  are... pretty much non existent. She could be pregnant but that would just push Fringe into soap opera levels.
 * You would think that the chances of both couplings producing a genetically-identical child would be negligable, but it obviously does happen. We still don't know the point of divergance for the two universes, but it clearly predates the births of most of the regular cast meaning that their parents had genetically-identical children at about the same time in both universes.
 * Yeah, but these people are probably born at exactly the same time.

Neither of the two universes is the one that will survive.
The Wave Sink Device is "a potential source of all creation, and destruction." Rather than destroying one universe to heal the other, it destroys both so that an entirely new universe can be born, possibly as some sort of cosmic cycle. Each new universe is automatically created with pieces of the device scattered around the world, and the radio signals detailing their location. Thus, when the new universe's humans reach the point where they can decipher the signals, the time to activate the device again is imminent. There is also a caretaker, or a group of them, who crosses from the old universe into the new one, in order to encourage the continued use of the device. is the latest of these caretakers, or perhaps has been the only one since the first use of the Device. The two universes are either the result of a botched activation in the previous iteration, or an activation-in-progress in the "alt" universe, which actually preceded the "main" one and will be destroyed when the process is completed, unless Peter chooses to preserve it, aborting the process.

Alt-Nina (or a shapeshifter) has replaced real Nina.
Which is why the show spent so much time focused on her apparently normal hand a few weeks ago.
 * She has a glove thingy...

Peter trained himself to ignore signs of the other world
Think about it: we've seen recently that Peter was, in fact, aware of the differences between worlds at a young age. Somewhere between kid!Peter and adult!Peter he started believing that everything was just fine. So, how did that happen? Presumably, Peter started believing his parents' version at some point, that he was extremely sick and imagining things. Thus, Peter subconsciously trained himself to ignore any slight discrepancies and any signs of weirdness. He had a lifetime of training himself to ignore any slight changes that would make him think his parents were clones. He trained himself to forget that he had bacon as a kid, he trained himself to ignore that he remembered a "Red Lantern" instead of a green one(and a Red Arrow), he forgot the Statue of Liberty was bronze and so on.

Thus, when Folivia arrived at the scene, Peter was already perfectly conditioned by a lifetime of training to ignore any weirdness, discrepancies from what he remembered, odd ticks or slight changes. He still spotted them to some degree - we've heard him confirm that - but he wasn't moved to react or really do anything. He instead trusted the assurances of Fauxlivia that she was moved to change by the other world, when it should have been blisteringly obvious that something wasn't right.

Prediction: sometime in the future Peter will be taken in by a shapeshifter(or some other doppelganger) despite there being clear signs that something isn't right. Alternatively, him spotting a shapeshifter without any foreknowledge, clues or help will mark a major character development moment for him.

Someone was treated with cortexiphan without Walternate's knowledge.

 * The yet unnamed recent arrival...  During "Bloodline,"   Cortexiphan is orange. Walternate and Alternate Brandon were having another pretty heated argument about using cortexiphan on children.   Do the math.

William Bell is the Big Bad of the series.

 * He's been manipulating Walter, Olivia, Peter, ZFT, the Shapeshifters and everything else to gain control over the Doomsday machine.
 * He knew about the device and tonnes of other things from Sam Weiss (see all of his WMGs).
 * The Soul Magnets not only allow Bell to survive his own death, but to inhabit the body of someone else.
 * The rapid ageing, originally cropping up in the Pattern (in episode 2 of the first season), allowed for Peter and Fauxlivia's child to come to term and be born safely within a very short space of time. It's likely the rapid ageing will continue.
 * Because the child has Peter's DNA, it can operate the machine.
 * If the child can somehow be dosed with Soul Magnets, Bell can inhabit his body and use the machine.
 * Furthermore, there's a lot of evidence that Bell is playing both sides against the middle. He took pieces of Walter's brain to keep him from remembering how to build the doorway between universes, and was apparently the only person who knew about it: if that's the case, how did Newton know where to find them? Why help Walter to prepare the cortexiphan kids, only to go to the other side and help Walternate create the Shapeshifters, only to then warn Olivia about their mission? His actions aren't merely neutral: he's actively fanning the flames of conflict between the universes. That suggests he's trying to accomplish some goal that's only possible when the universes are at war.
 * He also lied about how the Soul Magnets got in Olivia's system. Yes, when she came to his office on the other side, he gave her a cup of tea, but (and when I rewatched the episode, I double-checked) Olivia didn't drink it. Which presents several possibilities as to how he's possessing Olivia:
 * Bell dosed her with Soul Magnets himself at some earlier point in time, e.g. during the Jacksonville experiments.
 * Bell dosed her with Soul Magnets at some later point in time, while Olivia was in the alternate universe but before his death. This troper believes it's the most likely scenario: Bell may have developed the Magnets some time ago, and when he learned the circumstances of how the Fringe team crossed over and realised that his own sacrifice was the best/easiest way for them to get back, he dosed Olivia before sacrificing himself.
 * Bell has an agent who dosed Olivia at some point. This implies that Bell not only has an agenda, but people who agree with it and are willing to follow Bell's instructions after his death/disappearance. The most likely culprit is someone in ZFT, but that organisation may be all but gone after the death of David Robert Jones.
 * Olivia was never dosed with Soul Magnets. Bell's ability to possess her is due to something unique about her biology, or related to the cortexiphan trials. This raises further questions about who else he can possess, and whether or not he can possess Peter and Fauxlivia's baby.

Sam Weiss and the Observers are two different offshoots of the First People.

 * Sam Weiss is all natural. He was born, he's lived for ages and ages and is pretty normal by the standards of humans and First People. Somehow, he survived whatever happened to them.
 * The Observers are the surviving consciousnesses of First People who didn't necessarily physically survive whatever happened to them. They can't reproduce and they don't live forever, so they keep cloning their bodies and transferring their consciousness from one body to the next (ala the soul magnets). After however many years, the cloning process is becoming unreliable and the bodies aren't coming out completely right: the lack of body hair and similar facial features indicate that the bodies are losing their individuality, and the things they eat indicate that their senses are being dulled as well (in the first Observer-heavy episode, September orders raw meat and jalapenos and covers them with Tabasco sauce, and later refuses Walter's root beer float because he wouldn't be able to taste it).
 * August's badassery -- catching a bullet and starting a car by simply pressing his finger to the ignition -- indicates that he (and therefore the other Observers) have bodies that are artificial in some way. Compare them to the Shapeshifters, artificial beings made from organic technologies.
 * It's possible that in a roundabout way, the Shapeshifters are based on whatever technologies are used to build the Observer bodies. Sam Weiss knew William Bell. If Weiss is one of the First People, he probably has a very good understanding of the science used to create the Observers. Bell may have learned this science from Weiss and used it to create the Shapeshifters.

There will be a flashback episode in season 4 called "The Secretary".
It'll be all about Walternate, and show what he did in the years between learning about Peter's fate and travelling to the prime universe: how the alternate universe was affected and slowly began to fall apart, how society changed, how he became the Secretary of Defence, his opening moves in the war between universes and what (if any) relationship he had with William Bell.

The mysterious guy from 3x19...

 * Or alternatively...
 * For those dreading a Downer Ending...
 * For those dreading a Downer Ending...

Fauxlivia knows the guy from 3x19.

 * That's why he was in our Olivia's head.

Broyles will die in the season 3 final.

 * Walter did experiments with LSD that resulted in a woman basically revealing the existence of shape-shifters. Broyles' trippy little "death followed me" speech was actually Foreshadowing and "Lysergic Acid Diethylamide" will become the epitome of Harsher in Hindsight.

Ned the Piemaker is a cortexiphan kid.

 * Cortexiphan brought out his talent for bringing people Back From the Dead as a child. He almost exclusively wears black/white/grey (the exceptions are all undercover-type situations), and tries his very hardest to be inconspicuous. His greatest fear is becoming an experiment if found out-- but what if there's a grain of a memory in there? The supernaturally delicious pies may or may not be related.

Our Lincoln Lee is a Cortexiphan kid.

 * He's somehow related to Nick Lane and they went to kindergarten together.

The man in Olivia's mind (in "LSD") is:

 * Her birth father. The episode gave us more information on him than any other episode to date, and The Law of Conservation of Detail says that's important.
 * Another cortexiphan kid. One of the ones whose records were expunged. He's got Xavier-ish psychic powers, or he can enter dreams, or has some ability that allows him to remotely access Olivia's mind the way that Peter and Walter did in that episode. That's how he can be in her mind without Olivia ever having met him before.
 * Someone from the Alternate Universe. She accidentaly jumped at some point between the events of "Subject 13" and "Pilot", encountered this man and then repressed the memories as she's done for so many other Fringe-related things from her early life.
 * Will have 11 (or 12) fingers. Many of the glyphs from the eyecatches have turned up in the series (frogs and razor butterflies in "The Dreamscape", the leaf is Massive Dynamic's hand scanner, the seahorse in "The Bishop Revival" etc). I'm not sure if the hand glyphs are the same image reversed or two separate hands. It seems the man in "LSD" has 5 fingers on his right hand (holding the gun) but maybe he will appear differently in reality.

The first Fringe event on our side...

 * ...will be at Harvard just like in the alternate universe. And Astrid will be caught in the amber. Why? Because she's a much loved character with little impact on the plot, she means a lot to the Protagonist and the creators seem to really hate them at this point and because apparently the season final is pulling a Tonight Someone Dies.

Sam Weiss was lying out of his arse.

 * Having access to The First People document shouldn't give him so much information on the nature of the conflict between universes, or teach him how to build a window to the alternate universe. It's possible that he learned all this extra stuff from William Bell, but This troper still holds to the theory that Sam is one of the First People. Either way, he's lying when he claims that all he knows is what's in the First People book and a few missing pages.
 * I will agree and add that Sam seems much more knowledged and focused on his own then when he is with Olivia. On his own, he was condcting tests, taking notes and observing things. With Olivia, he is just running on "I don't know. I just read the manuscripts". With a bit of Fridge Brilliance, you could make the claim that Weiss was frustrated in this weeks episode not because he has no idea like he claims but that he can't find a way to shake Olivia off and go back to working on his own.

The show will end with Walter going back in time, erasing the events of the entire series in the process.
Despite all efforts to fix or neutralize it, the damage to both universes will be so great that both of them will eventually collapse on themselves and be completely annihilated.

Walter, realizing he has to give up his son to save both worlds, decides to go back in time (into his past body) and finally accept Peter's death. He never goes into the alternate universe and destroys the technology, but the memories and horrors of a time-line that never existed will haunt him for the rest of his life. His universe is saved.

Because Walternate's Peter wasn't taken, he later died... and Walternate thus does the same thing that Walter once did, and opens a portal to an alternate universe (not Walter's, since Peter has already died there, but a third one not seen in the series). And thus, though some of the characters may be somewhat different, it all begins again.

Peter was acting strange in "The Last Sam Weiss" because he had just come back from the future.
Wibbly-wobbly timey-wimey. Let me explain. That's the best sense I can make out of a sequence of events I found really confusing (though really cool to watch).
 * The audience never got to see the original timeline. In that timeline, Peter stepped into the machine on Liberty Island, and used it to start tearing holes in the alternate universe, trying to destroy it before Walternate could use the alternate universe's machine to destroy the prime universe.
 * From there, events unfolded just as they were described/portrayed in "The Day We Died". Knowing he was beaten, Walternate came over to the prime universe on a mission of mercy. The alternate universe was destroyed. Without it's yang, the prime universe began to break down. Walter was jailed and then released. Olivia was murdered by Walternate. Walter and Peter agreed on the plan of trying to change the past by having Peter go back and not decide to destroy the alternate universe.
 * Using the machine and probably his research from pre-St. Claire's, Walter figured out how to send Peter's consciousness back in time. It anchored onto the point in time when his mind was completely calm and blank: during his coma after touching the machine's force field. The two consciousnesses were scrambled together, similar to how Olivia and Bell's were, but because they're both from the same person in two different points of his personal timestream, the conflict was less noticeable. That's why he was confused ("where/when am I?") and why he instinctually went to Liberty Island (he remembered going there 15 years earlier).
 * It was only when Peter actually stepped into the machine, like he'd already done 15 years earlier, that he remembered everything about the Bad Future he'd lived through. Knowing what would happen if he just did the same thing again, he instead chose to merge the two Liberty Islands and bring the conflict to a peaceful resolution.
 * I took it to meant that Peter was channelling both versions of himself. He went to a numanist (dead!Peter collected coins) but he believed Walternate was his father (technically true for alive!Peter). IMHO, this foreshadowed his joining the two universes at the end of "The Day We Died".

Olivia will become a Willing Channeler

 * Olivia has already shared consciousness/been possessed three times in the series so far: John Scott (season 1), empathic cortexiphan subject Nick Lane ("Bad Dreams"), and William Bell (season 3). At the end of season 3 Peter never existed anymore, but Olivia may be able to bring him back through this talent.
 * Okay, that's not how Peter returns, but the possibility of this power still remains. Olivia's time spent brainwashed as Altlivia is also similar, and the presence of the Mysterious Man In Olivia's Mind ("LSD") suggests that she is rarely alone in her own mind.

Fringe and Primeval take place in the same universe

 * In the Bad Future of there is mention of a giant wormhole leading several milion years in the past. The dino-wormholes in Primeval are the result of the two (or more) universes coming into conflict. The Primeval team is Britain's version of the Fringe division.

Reserved for predictions about changes to the timeline
Confirmed changes: Speculation:
 * Walter is a shut-in in his lab.
 * Olivia is as uptight and professional as she was in Season 1, if not more so.
 * Olivia killed her stepfather.
 * Fauxlivia's twin switch with Olivia was completely changed; Olivia was only imprisoned rather than brainwashed to believe that she was Fauxlivia
 * There was no Cortexiphan Brigade of Peter-rescuers because not only did Peter not exist as an adult, None of the Cortexiphan children were discovered by Fringe team.
 * Alt-Broyles is still alive because of this.
 * Similarly, Fauxlivia never seduced Peter and thus never got pregnant by him, and thus her relationship with Frank is still around.
 * Peter died when the ice cracked after Walter brought him back to our universe.
 * Bridge between universes was created when Walternate turned on the machine, rather than because of Peter's choice.
 * None of the Cortexiphan cases happened, as evidenced in "Subject 9" when the titular character asks about others and is told that he's the first one Fringe Team has found.
 * Olivia has known Nina Sharp since childhood now.
 * Olivia has known Nina Sharp since childhood now.
 * Olivia's cortexiphan abilities have been reset; she hasn't been activated. Based on that Olivia is back to wearing color- Olivia would wear navy suits and light blue or rust red shirts in Season 1 before being activated.
 * Confirmed: None of the cortexiphan children were activated, as Olivia ran away during the events of "Subject 13" because Peter wasn't there to get her to confide in Walter, and because of her escape the trials were simply ended inconclusively.
 * Actually, the trials ended years after Olivia left, perhaps due to the fact that Walter had lost both Peters. It's not explicitly stated that the trials ended because she ran away.
 * The other cortexiphan kids have their "side effect" powers (since everyone else was said to have side effects), but they have no control and are also much weaker, hence not being involved in any Fringe events.

There is only one copy of the Observers throughout history (i.e. no time-cloning shenanigans)
This would explain why they are exempt from most rules of time travel, and why they are able to change the timeline with such ease. This in particular provides an explanation for how they could erase adult-Peter from the timeline so easily - September simply went back and replaced his earlier self, making a different choice.

Peter'smeans that August is still alive

 * Walter never talked him into "making the girl significant", so he never died. And because he didn't sacrifice himself, she died. And somehow, he's the one that
 * Peter . The rest of the WMG still applies, though.
 * I don't know. Since they are unaffected by the timeline change, August's death probably still holds.

The Observers will be forced to

 * Now that he's, they'll either see things resetting on their own and just fix everything at once before something causes a paradox somehow, or they'll try to  but fail due to internal opposition and/or   being somehow resistant to whatever they did to   now.

The Bishops are Sparks

 * Nobody's put this up before? I'm amazed. Anyway, they're a family that somehow manages to "break through" later in life than other Sparks of comparable strength (which causes their first creations to be much less dangerous than other Sparks'). Walter's "breakthrough" was his first success in fringe science, or maybe cortexiphan, and Peter's has yet to appear.

The Observers will go to war with Fringe Division.
Now that Peter is back in the altered timeline, you've got the threat of how wibbly the universes can become as a result of Peter being around (the reason why he had to be Ret-Gone'd in the first place) plus the threat of the time paradoxes that could occur with two seperate timelines (of two seperate universes) overlapping. To stop Peter from wreaking further havoc, the Observers will take direct action and try and kill him, putting them in direct conflict with Fringe Division.
 * Now that the Alternate Universe isn't the Big Bad anymore, the only major element of the Myth Arc that can take centre stage is the Observers, so it makes sense that they'd become the new Big Bad. It'd also create a good opportunity to explore just what the Observers are.

While the alternate universe in general no longer acts as the Big Bad, Walternate has personally stepped up his game.
Walternate's just hiding a new set of truths, and the Red 'Verse Fringe Division is still in the dark about Walternate's activities and the true nature of the two universes. Which informs the next WMG ...

Walternate cloned Red!Peter after his disappearance (or even before).
In this preview for "Back To Where You've Never Been", there's a blue flash at 0:37, right after Walternate says "Not everything is as it seems." If you freeze the video, it shows a room with eight vertical tanks. They each appear to contain an adult human male in some kind of stasis (the figures in fluid and fitted with breathing apparatus). Peter's illness was genetic; Walternate was working on a cure; therefore, Walternate doubtless had Peter's genetic information on file. It's hardly out of the question that he would make use of it.
 * The full episode reveals they are human shapeshifters created by.

Nina Sharp is exploiting Olivia and her abilities in order to find William Bell.
She adopted Olivia (and Rachel) in order to continue the cortexiphan experiments, and stepped them up once Peter arrived from limbo. Why would she only do this now? Because Peter travelling from one timeline to another opens up the possibility of travelling to other parallel worlds (either alternate universes or alternate timelines) beyond simple the redverse. Olivia's cortexiphan ability is being able to safety travel between universes, so Nina is stepping up the experiment to see if Olivia can help her travel to these other worlds. Why would she do this at all? William Bell is dead in this timeline, but almost certainly still alive in others.
 * Alternatively, she's trying to recover the soul magnets from the original timeline.

The Watchers will not be explained
It will never be fully explained if the Watchers are descendants -genetic or memetic- of humanity, of the shapeshifters, or something else, it will simply be implied they appeared after the Technological Singularity and therefore cannot be comprehended by pre-Singularity minds. The one thing that will become apparent is that they need at least one of the universes to be stable enough to achieve singularity for them to exist, that's why they appear most frequently during events of unbalance, going as far as to intervene if the unbalance goes too far. The exact events of their absolute past are not important as long as a singularity happens, but the exact events of their absolute future are important, that's why August's death made the girl important; the reason for this cannot be understood.
 * What?
 * Fairly simple to understand. One of the verses experienced The Singularity. The Observers are beings that came into existence in that universe's timeline after said singularity, or in other words the future. They're present in the, well, present so they can make sure the singularity takes place, creating a Stable Time Loop (they go back in time to make sure they come into existence). We can't really understand what they're up to because we haven't had a singularity ourselves, while they have, hence they're not as human as us. Or something.
 * Concise Troper is concise, and thank heavens for that.
 * Partially Jossed in that they were explained, partially confirmed in that they are humans from one of many possible futures. Didn't say anything about the Singularity, though, just that they had the tech for travel through and outside of time, and that they liked observing important events.

August is alive, but is not the same August and he is keeping the timeline from becoming fixed
The Observer seen at the end of Forced Perspective looked a lot like August, at least what could be seen in the angle of that shot. But besides that -and this could have been just on my TV, or due to the lighting-, he seemed to be wearing a brown suit instead of a black one. If he was in fact August, then it would seem that the Observers are not completely immune to changes in the timelime. If he was in fact wearing a brown suit, that could mean he was an Observer specific to the amber timeline, as in created because the original or absolute August died, but the interactions he had in the original timeline that lead to his death were erased; maybe this change is powerful enough -the deletion of events leading to the death of an Observer- that it ends in the creation of a copy, or new version, of the deceased Observer, so that the death of the original still happened and the internal Observer causality is not affected, but a new version appears to satisfy the causality of the new timeline. This could mean there is at least one new kind of Observer, brown!August. Also, perhaps brown!August is an anomaly whose existence is keeping the amber timeline from becoming stable, which was the reason Peter was able to come back. And perhaps brown!August's existence will be revealed as a threat to the stability of the Observer's internal causality.
 * Pretty sure they would have changed the actor or the suit, but not both.

Olivia's stepfather has/had/will have again? abilities similar to her own
Assuming that at some point another timeline reset will have him alive again, one is forced to wonder about his taunting visitations each year on Olivia's birthday. Each year, he breezes past the (likely ever-increasing) precautions of a trained FBI agent, leaving no traces of how he did it. Now, granted, he knew her when she was young, and a control freak knows habits, and he wasn't depicted as being truly stupid. But nor was he depicted as being someone at or near any of the genius characters seen. So how better to go around all her efforts than to go around reality itself? How he got this power I have no idea - maybe he's really her uncle, ala another JJ Abrams effort. Again, could be just planning on his part--but this is Fringe.

David Robert Jones is trying to turn Olivia into an Observer.
Perhaps unintentionally but he is interested in the full array of her powers which have probably not even truly started to be tapped.
 * Does he know about the Observers? IIRC, Amber!Jones is pursuing the same thing as Blue!Jones in the first season, who was activating all the other Cortexiphan kids he could track down. However, I am intrigued at the idea that Olivia could be a precursor of the people who eventually become the Observers.

September will play an important part in the season/series finale.
We've seen him die/get whisked away/whatever, but we haven't seen how he got injured. Five'll get you ten it happens during the inevitable season-ending showdown.

Transformers Prime is all one of Walter's long LSD trips.
John Noble plays Unicron, one of the Big Bads in the show, and it's not hard to imagine someone under the influence of drugs imagining he's an evil Satan Expy robot who comes out of a volcano and tries to crush things.

In the next episode (that is 4x18)...

 * David Robert Jones will incapacitate Peter Bishop and destroy the bridge so that the two universes can't communicate with each other any more. In the trailer, we see shapeshifter!Broyles walking up to the machine and in 4x17 Fauxlivia mentions that the alternate universe is getting better because of the truce. Jones is trying to destroy the alternate universe to heal our world but he doesn't know that destroying one universe will destroy the other. Meana was helping Jones so that she'd end up on the side that survives.
 * Also, since Fauxlivia is spending the episode on the other side, she'll get stuck. Bonding with the other team will follow.

Fringe is a darker and edgier retelling of Futurama
It makes perfect sense. Crazy mad scientist, action girl whose alternate-universe counterpart has red hair, scientist's relative whose unusual birth circumstances grant him an important ability, the only non-white people are the bureaucrat and the mad scientist's assistant. Clearly Gene will be revealed to be behind the entire series.

This season will end with a Revival Loophole being pulled
September said Olivia needs to die. He didn't say she cant come back.

William Bell knew that Olivia was left behind in the other universe in Season 2.

 * He needed to activate her abilities.

Olivia's will die in Season 5

 * She was nowhere to be seen in Letters Of Transit and September's words tend to come true when you least expect it.