Donna: How about you, are you all right?
Donna, our favourite stroppy Londoner, has been having some funny turns recently. As we all know, she's happily married with two kids, but lately she's been having "lost time" and Dr. Moon says everything is fine, and...
But what about the library of the future, and the people-eating shadows, and River Song and everything? And then, we see a familiar person in Donna's world: Miss Evangelista, one of the Red Shirts killed in the last episode. And she tells Donna that none of this is real.
Miss Evangelista takes off her veil and reveals that her face has become glitched. The little girl, watching all this on her TV, screams. So do you, because, Steven Moffat.
Donna and everyone else aren't really in present-day London. They're in a Lotus Eater Machine, and the computer is getting a little overloaded. Doing what? Saving all the people, of course... that's where they all went. They got saved... to disk. When the Vashta Nerada arrived, the library's computer tried to teleport 4022 people out all at once, and the system overloaded. Even the neural echoes of people, briefly captured by their suits' comm systems, get included. Which is how Miss Evangelista now lives on.
The Vashta Nerada usually live in forests. They hatch in trees. Trees... that were made into a planet full of books.
The little girl really was a little girl: related to the founder of the library, she was merged with the library's computer as a gift to her when doctors couldn't save her life. Her therapist, Dr. Moon, is quite literally the planet's moon, which stabilizes the computer from above.
While the Doctor, back in the real world, works all this out, a couple more people get eaten by the shadows. The Doctor teaches the Vashta Nerada how to use the suits' comm systems to communicate, but it doesn't exactly help. He does, however, convince the creatures to give him one day, and after that, they can have the planet all to themselves.
River knows the Doctor's name. His real name. Just as the Doctor realises that he's encountered someone who will eventually mean a great deal to him, he also realises that he'll need to pull a Heroic Sacrifice to rescue Donna and the rest of the saved people. River punches him square in the face, handcuffs him to a wall and sacrifices herself instead. Because she knows that if the Doctor would sacrifice himself this way, he wouldn't be able to regenerate, as the machine's continuous shock would kill him permanently in the middle of regeneration. And now she knows that this is not only his first time meeting her, it's also her last time meeting him... and that from his perspective, their entire relationship will have been based on the moment the Doctor saw her die.
All the not-dead people are transported back to the library. Donna desperately searches for her Matrix-world husband, whom she truly loves. But just when he sees her, he's teleported away to his own home, and she decides he must have been imaginary. The Doctor leaves River's diary and her version of the screwdriver behind in the library --
-- she knew his name. He gave her his screwdriver. Why did he give her his screwdriver? Because the screwdriver has a neural relay with her mind's echo stored inside it. The Doctor races back to the little girl / computer and plugs in what's left of River. Her echo, and those of her loved ones who died today, can live on forever in the Matrix system. In a very bittersweet way, Everybody Lives.
- Alternate Character Interpretation: After The Impossible Astronaut, River's sacrifice in this episode starts to look like suicide, as the Doctor doesn't know who she is anymore, and she realises she'll never see him again.
- Is there any reason it couldn't be both a Noble Sacrifice AND a Driven to Suicide?
- After A Good Man Goes To War, it is apparent she had literally no acceptable option but to prevent his death and was the only viable substitute for him.
- Ask a Stupid Question: "It's a screwdriver. It works in the dark."
- Badass Boast: Indirectly, and the more badass for it: "I'm The Doctor, and you're in the biggest library in the universe. Look me up!"
- Because You Were Nice to Me: Miss Evangelista's reason for wanting to help Donna escape her false reality.
- Brain Uploading
- Call Back: River's end-of-episode speech has her quote the 9th Doctor: "Everybody lives."
- Chekhov's Gun: The screwdriver. He gave her his screwdriver.
- And she told the Doctor his own name.
- What's scary is, over two years later not only have we still not seen how either of these go down, and the latter is now a major plot point in the series, but they serve their purpose as a part of the next Doctor's story.
- Conspicuous CGI: Played for Drama. Evangelista's face is literally glitched. She looks badly Photoshopped, which is exactly the point.
- Cuckoo Nest: Dr. Moon tells Donna she hallucinated the Doctor, but is now cured.
- Dashed Plotline: Donna's life inside CAL is a subversion. It looks like we're only being shown selected scenes that take place years apart, but then it turns out that Donna is only experiencing those scenes as well...
- Eureka Moment: "Why would I give her my screwdriver?" And dear God, it is GLORIOUS.
- Everybody Lives: Done a bit differently, in that the dead end up living in Cyberspace instead of the real world, but Word of God is that Moffat considers this to be as much being alive as most of us get.
- Their consciousnesses exist inside an electronic library containing the sum total knowledge of a huge slice of the Universe. They can virtually go anywhere, be anybody, experience anything… Sounds pretty good.
- Foreshadowing: Dr Moon seems to maintain the dream-world's integrity at several points, but it only then dawns on us what he represents when the Doctor is told that the Moon that's rising in the sky isn't real, its an artificial Doctor Moon who maintains the library database.
- Curiously River Song's in this and the previous episode makes many sly references to events and dialogue spoken in The Eleventh Hour… Spoilers!
- Another sneaky bit of foreshadowing for Season 5: "Time can be rewritten!"
- River says she trusts the Doctor to the end of the universe... and actually, they've been.
- She's seen whole armies turn and run when the Doctor arrives, and we're starting to get an idea as to why.
- Something of a Book End: River knocks the Doctor unconscious and handcuffs him to a pole. Guess what her mother does in The Eleventh Hour.
- Also, one that has yet to come full cycle, a reference to The Fall of the Eleventh at the Fields of Trenzalore, referenced again four years later:
The Doctor: There's only one reason I'd ever tell you my name. There's only one time I could.
- Green Aesop: You cut down a load of trees, make the trees into books, put the books in a library… and then get eaten by the shadows that hatch from the books!
- Space Whale Aesop
- Also either a Broken Aesop or a Family-Unfriendly Aesop. Books, reading and libraries are supposed to be good for you, and certainly non-threatening. Apparently, though, making libraries too big is dangerous. No, not because knowledge is power or something like that, just because all that wood pulp contains the seeds of air piranhas.
- Almost surely not so much Broken or Family Unfriendly as just plain not intended to exist. Bringing in the Vashta Nerada was a horrifying, horrifying tragic accident. These things happen in the Whoniverse.
- It being an Accidental Aesop is made extremely likely by the Doctor spending the beginning of the episode before going on about how books are awesome even though there are all kinds of digital and holographic ways to store them and never once does he say in any way shape or form that it was wrong for the books to be made.
- Heroic Sacrifice: River Song.
- Holodeck Malfunction: sort of.
- Hope Spot: Donna really loves her virtual husband, and promises to look for him in the real world as she's yanked out of the computer system. In the real world as everyone is restored, she seems to have already given up on this. However, he sees her and tries to call out her name, but is halted by his stutter and is teleported home before he can reach her.
- I Know Your True Name
- Informed Attribute: CAL loved books more than anything. That must be why we never see her reading any, instead always drawing or watching TV. (To be perfectly fair, she had just seen THE DOCTOR—a.k.a. the stranger she saw in her head—in the TV.)
- Also she was in sleep mode with her mental energies already at capacity trying to sustain those people. She litterally wasn't herself at the moment
- Insane Troll Logic: "If he dies, I'll kill him!"
- Jerkass Facade: Strackman Lux, set up as a paranoid, un-co-operative type obsessed with patents and IP, but it's all a front to keep CAL safe—he's actually quite nice.
- Leaning on the Fourth Wall: The scenes appearing on CAL's TV, complete with music. She, like many of the viewers, spends a good part of the episode clutching a pillow and trying not to scream.
- Time in the computer progresses "like a dream"—people just mention where they're going to be, and then they're there. In other words, it's like television. Cutting between scenes in a conventional way, and then revealing that that's how the characters are experiencing it, adds a meta level to the are-you-sure-you-know-what-is-and-isn't-real theme.
- Living Shadow - Invisible air piranhas, who are very light-sensitive (or maybe just appear as shadows, and are very slow-moving) but can strip the flesh from a chicken leg in the time it takes to fall to the ground. And they learn quickly...
- Lotus Eater Machine: The imaginary world created by CAL.
- Meaningful Name: CAL is an acronym of the girl's full name. Also, there's Dr Moon, the doctor moon.
- More Expendable Than You: River takes out the Doctor to do a Heroic Sacrifice in his place.
- Nice Job Breaking It, Hero: CAL. First she (inadvertently) "kills" her father after being upset at The Reveal. Then she tries to break the remote, triggering the self-destruct mechanism. Then she "kills" Doctor Moon, on purpose, when he tries to stop her. Granted, she's been hit with the Tomato in the Mirror, and Doctor Moon recovers but still.
- It isn't necessarily an unexplained recovery since all we know is that she removed them from her virtual reality, it isn't ever indicated that she deleted them.
- Orphean Rescue: Getting Donna back out of the computer.
- Painting the Fourth Wall. Donna starts noticing the episode's editing when she's in the computer. This is because the cuts represent the computer basically teleporting her and giving her Fake Memories.
- Papa Wolf: Though technically the little girl who Strackman Lux is willing to go to such lengths to protect is his aunt.
- Platonic Cave
- Powered by a Forsaken Child: The Library exists for the sole purpose of keeping CAL occupied, which makes this an inversion.
- The library itself is an inversion - there is a child with a terminal, incurable illness, but her family is rich, so her brain is uploaded and she is given a library the size of a planet to keep her entertained. However, when something threatened the people in the library, they all tried to teleport away at once and wound up getting stored in the computer. That was causing problems for the child, so in a way the lifeboats were Powered by a Forsaken Child.
- Self-Destruct Mechanism
- Ship Tease: The Doctor and River.
The Doctor: Oh, I like you.
- Also an echo to all her earlier/later mutual exchanges of "Oh, I hate you" - "No, you don't" with the Eleventh Doctor.
- Even the fact that River is going to die in a few moments doesn't stop her from dropping one last Double Entendre.
Doctor: Why am I handcuffed...why do you even have handcuffs?
- Spooky Silent Library
- Stable Time Loop: The Sonic Screwdriver, among others. Many of River Song's mannerisms and rules, including Spoilers and the blue diary, she initially got from the Doctor, who in turn got them from her. We see one "end" of the time loop here, and the other in "Let's Kill Hitler". Another example is the way of opening the TARDIS by with a click of the fingers; it seem the Doctor hadn't even thought of doing that until River mentioned it.
- Tear Jerker: "You and me, time and space. You watch us run."
- River says "I hate you sometimes," and the Doctor says "I know." HE'S NOT SUPPOSED TO SAY 'I KNOW!'
- Too Dumb to Live: The metric that "Other Dave" was told to pull The Doctor out of his first talk with the Vashta Nerada.
- Trust Password: River manages to convince the Doctor to trust her by telling him his real name.
- The Un-Reveal: River Song knows the Doctor's real name, but only whispers it to the Doctor. We never hear it.
- Wham! Line: "River, you know my name."
- Wrong Genre Savvy: The Doctor just lets Other Dave stand there while he's talking to the Vashta Nerada! You're better than that, Doctor!
- The X of Y