Happy birthday, "Doctor Who!" In celebration of the sci-fi series reaching the big 5-0, the BBC pulled out all the stops. Between the simulcast taking place internationally, on television and cinema screens alike, the nearly incessant "Who"-related media on the BBC channels and BBC America and over a year's worth of hype, Nov. 23 was set to be a spectacle. 

Written by showrunner Steven Moffat, this episode brought back Tenth Doctor David Tennant and Billie Piper, playing the the spirit of a sentient weapon of mass destruction, in the form of the Bad Wolf. The Bad Wolf is Rose Tyler's super-powerful, omniscient form, taken upon looking directly into the Time Vortex (an act which, you will remember, spurred the Christopher Eccleston's Ninth Doctor into regeneration). The episode also introduced the War Doctor, played by John Hurt, and the current Eleventh Doctor (Matt Smith) and his companion Clara Oswald (Jenna-Louise Coleman). Also, Queen Elizabeth I. Two of them, in fact, both played by Joanna Page ("Breathless," "Love Actually").

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This had three timelines: the present, beginning with newly-minted schoolteacher Clara (with a motorbike, no less!) reuniting with her Doctor after an unspecified length of time. The TARDIS, with Eleven and Clara in it, are then snatched up by a UNIT helicopter, with a return appearance from UNIT's scientific advisor Kate Stewart (Jemma Redgrave), daughter of Third Doctor's companion Brigadier Lethbridge-Stewart, or, the Brigadier (Nicholas Courtney). At the base in the Tower of London, Stewart reveals to the Doctor and Clara that the glass of strangely 3-D paintings in the "Undergallery" of the Tower of London has been broken, and now, several of the painting's subjects have disappeared. The Doctor explains that the glass was broken by the inside and whatever was in those paintings broke out.

Interrupted by a time vortex, we see Eleven (and a fez) meet up with Ten and Elizabeth I, who had been courting (and then escaping from aliens) in 1568 England. This is a riff on the recurring Noodle Incident of the Russell T. Davies' era, when the Doctor married Elizabeth I and left her at the altar, saying he would return soon. (He never does, the cad.) At the time, Ten is trying to differentiate between the original Queen Bess and the shapeshifted copy, a part of a Zygon plan to invade the Earth. The Zygons (and Elizabeth's storyline) fade into the background, unfortunately, especially when Eleven arrives and begins bantering with his past self. 

In the future/all of time, we have a third incarnation of the Doctor, this time played by John Hurt. On Gallifrey, the Time War between the Time Lords and the Daleks rages on, and the Gallifreyan city of Arcadia is burning, prefaced by the minisode "The Last Day". The Time Lord army is failing to keep the onslaught at bay, and thousands of Gallifreyans are fleeing the doomed city, to the dismay of the Gallifreyan commanders, whose High Council has "other plans" and is useless or simply unhearing to their plight. Cue the Doctor, whose regeneration we saw in the minisode "The Night of the Doctor," deciding that enough is enough. "No More," he shoots into the wall, a message to the commanders, and then he proceeds to steal an ancient, powerful Gallifreyan weapon from the stores. He travels to a deserted planet and activates the weapon, which is so powerful that its operating system is sentient, and takes on the form of the Bad Wolf. She tells him that there will be consequences to using the weapon, which will wipe out both the Dalek race (...kind of) and Gallifrey, a body count of billions placed squarely on the Doctor's shoulders. When he says that he has no desire to survive the use of the weapon, that the guilt would be overwhelming, then she tells him his punishment for its use: he must live with what he has done. She shows him his future, should he use the weapon, and transports him to the same English forest where Ten and Eleven have met. 

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After being thrown in a cell together, the Doctors confront their warrior past, without realizing that this War Doctor has not yet used the weapon. The War Doctor finds Ten and Eleven immature, with Ten seeming mercurial, manic and melancholic at once, and Eleven seeming uncaring about his past—he claims he never bothered to count the number of children who were on Gallifrey the "last day." The Bad Wolf asks the War Doctor if he wants to be this in his future: "the one who regrets and the one who forgets."

Another scenario of mutually-assured destruction appears in the midst, with three Zygon clones confronting their three UNIT officers doppelgangers, under the countdown of a nuclear warhead beneath the Tower of London. Kate Stewart, in order to save the world, would be willing to take out the whole of London if it would mean that the Zygon invaders would perish with her. The parallels to the Doctor's decision for Gallifrey are not subtle, but they are emotionally packed. Neither side is willing to blink first, so the Doctors (Ten and Eleven) prepare to negotiate a peace treaty, under the circumstances that no one can remember whether they themselves are Zygon or human, allowing for complete objectivity. Realizing the error of her (their?) ways, Zygon!Kate and human!Kate agree to call off the strike.

The sight of his future incarnations negotiating peace between two sides ready to fight to the death opens the War Doctor's eyes. Despite the violence he is about to do to the Daleks and the Gallifreyans alike, if his actions result in the two versions before him, workers of peace, then he must use the weapon. Clara, observant as she is (although fading into the background, a bit, at this point, given the spotlight on the Doctors in this episode), realizes that this Doctor has not yet pushed the button, so she has a chance to stop him. But before she can change his mind, he is gone, with the (unseen) Bad Wolf, back to the deserted planet. 

At the crucial moment of his decision, as the War Doctor prepares to commit genocide on two sides, Ten, Eleven and Clara appear before him, saying that he should not have to do it alone, agreeing to do it together. But at the last moment (and with some words of persuasion from Clara), Eleven decides that, after 400 years to think on his past actions, he changes his mind. The three Doctors try a plan B: together, they can lock Gallifrey into a moment of time, safe in a pocket universe, with all appearances of having been destroyed. The Daleks will kill each other in the crossfire, and Gallifrey can be saved, but they would have to do it together, and precisely. 

Cue a montage of all 13 doctors (including Hurt and a surprise appearance from upcoming incarnation Peter Capaldi) working together to save Gallifrey, with all the triumphant music and swelling emotion the 50th Anniversary deserves. The problem is, when all is said and done, none of the three Doctors there that day will remember their actions, due to the paradox, and they will never know if they were successful and Gallifrey is safe and sound, or if it burned and their plan failed. This is the kicker: it avoids ret-conning the whole of the past 7 years of the show, because if the Doctor doesn't remember his actions due to the paradoxes of having three Doctors in one place, then he will believe he has killed the Time Lords. The continuity previously at risk does not change. 

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Hurt returns to his TARDIS and begins regenerating—he's no longer necessary—and though we don't see the end of the regeneration into Christopher Eccleston's Ninth Doctor, it's implied that he does, given the War Doctor's birth from the Eighth Doctor (Paul McGann, in "The Night of the Doctor). Ten implores Eleven to tell him of the future, what it is that frightens and dismays Eleven, and Eleven explains that Trenzalore is upon them, and he has seen their grave there on the battlefield. Ten departs, with a kick-in-the-gut goodbye of, "I don't want to go" (I will never be over Ten's regeneration), leaving Clara and Eleven alone in the art gallery, standing before the painting of Gallifrey frozen in time, wondering if their actions were succesful or not.

Clara gets into the TARDIS, and Eleven is met by a curiously familiar figure, the curator of the art museum (played by Tom Baker) (TOM BAKER) tells him that there is no need to wonder. The Doctors had presumed that the title of the painting was either "Gallifrey Burns" or "No More," but the curator, with a familiar nose-flick and a smile, says that it's actually titled "Gallifrey Burns No More." 

Because the other Doctors had left already by the time this happens, only Eleven knows the truth—it's in the others' future, but his future is upon him now, setting him up for a potential story arc: perhaps he will go out in search of Gallifrey?

With a nice little monologue about dreams, Matt Smith's Eleventh Doctor joins all 11 other incarnations of the Doctor on a misty spacescape, ending the episode with an image of all of them together, for Classic and New Who fans alike. At this point, I think I was probably hyperventilating, and I know I couldn't feel my legs, because all the blood was speeding to my rapidly-beating heart. 

The episode was rich and decadent with references to the past (the UNIT officer's familiar scarf, for example, amongst other, more subtle shout-outs), and what could've lead to a paradox was figured out with some use of Deus Ex Amnesia and a bit of Bad Wolf magic. It wasn't perfect, by any means; Elizabeth's story was forgettable and a little overdrawn, and the Zygons, though a nice parallel, were far less interesting than the moral quandary of the War Doctor. Special note should go to Billie Piper as the Bad Wolf; while I know some were hoping that Rose Tyler make an appearance (and you could argue that she did, given that the Bad Wolf is simply a version of Rose), I'm kind of okay with the fact that she didn't. Rose is happy and safe in the parallel world with meta-crisis Doctor, Ten-Too, and she doesn't need to be pulled back. Furthermore, I don't think you could bring her back without bringing back all sorts of other question, and regressing Eleven's character development back into the melancholy of Ten. After spending several series being sad about never having Rose again, Ten moves on—she's happy; he's regenerating, and that's okay. Things continue. Eleven married (and subsequently lost) River Song; he's with Clara now, and things must keep moving forward. 

Some are going to feel conflicted about the fact that it wasn't a completely self-referential pat-on-the-back for the whole of the 50 years of show, but I don't think that would've been a good episode at all. It would've packed too much into 75 minutes, but it would also keep the show in the past, whereas we should be looking at the next 50 years as well as celebrating what has come before. There needs to be a balance—it wouldn't feel like an anniversary without the past, and aside from the images of past Doctors, this episode broke down the biggest quandary of the New Who series: the Time War, what happened, and why it had to happen. But it also set up for future episodes, including the dreaded Christmas special, when Matt Smith will wear the bowtie for the last time and usher in Peter Capaldi. 

You can reach Staff Reporter Christine Bancroft here or find her on Twitter here. She's going to go have a heart attack now.