Obvious note: Spoilers.
So, we’re out in space, spinning around an unimportant blue/green planet, surrounded by the combined armies of all of the terrifying space rotters there have ever been (and the Tereleptils). They’ve been drawn there by a mysterious signal, one that really seems to push their buttons, or in the case of the Daleks, aggravate their tentacles.
On one of the ships, a man in a cloak waves a Dalek eyestalk and makes heraldic pronouncements of heroism and comradeship, except it turns out it’s a Dalek ship, so it’s all a bit of a faux pas. It’s the Doctor! And he’s got a teleport device, seemingly run by a disembodied Cyberman head he calls Handles (because of the handles).
It turns out everyone is drawn by this message, but no one knows what it means. The Doctor’s telephone is not patched through his console, and he spends some valuable time bickering with Handles about it, when he should be answering the phone to Clara.
It’s Clara! And she’s told her family she’s got a boyfriend. So the Doctor has to put aside his investigations (which largely involve being shot at, by Cybermen this time) to go and help her cook a turkey.
The problem is, he’s naked, apart from some hologram clothes that sadly don’t seem to work on everyone. An awkward silence (not that sort) falls on the dinner table, while Clara and the Doctor rush the turkey into the TARDIS to cook it.
Handles has some disturbing information, this unexciting planet, shielded from entry, is somehow Gallifrey. This infuriates the Doctor, who is adamant it can’t be. His sulk is interrupted by the foghorn blast of Tasha Lem, Mother Superious, whose Church of the Papal Mainframe are responsible for the shield around the planet.
Luckily she and the Doctor are old friends, and she invites him aboard (but not before Clara has to reluctantly don a hologram wardrobe too). The Doctor and Tasha sneak off for a confidential head-to-head, which leaves Clara facing a Silence or two, or one, it’s hard to be sure when your memory keeps going.
While this is going on, Tasha explains that the signal from the planet has made everyone who hears it feel afraid, hence their aggressive reactions. It’s coming from a human settlement, a farm on the surface that would be entirely wiped out if the Papal Mainframe wasn’t standing in the way. For some reason this makes both the Doctor and Tasha very excited, and Clara’s interruption has a certain fruity tang of gooseberry.
The Doctor and Clara teleport down to the surface, after the Doctor has had to surrender his key so the TARDIS can’t come down. It’s snowing when they arrive, and Clara spots some cold arms coming out of a drift. Just a statue, phew!
Oh wait, a statue? It’s the Weeping Angels! Luckily the Doctor has a spare TARDIS key hidden under his… wig?
[Let's just pause a moment to reflect on the Doctor and his wig.]
[Ready to continue? On we go]
Safely unbalded and clothed, the intrepid pair head into town, which is called Christmas, and discover that there is a truth field running through the community. Then the Doctor discovers a very, very familiar crack in the wall. That same crack that forced him to reboot the entire universe.
It seems that Gallifrey is trying to get back into the universe, and they’re using the crack to do it. Using the Seal of the High Council of Gallifrey (nicked from the Master), the Doctor forces Handles to interpret the signal. It’s the oldest question in the universe, hidden in plain sight. “Doctor who? Doctor who?”
And that leaves the Doctor in something of a pickle. As soon as he speaks his name, Gallifrey returns, and if the Time Lords returns, hell is coming with them. But all of the invading armies above want to destroy the signal, to prevent this from happening. And stuck in the middle is this festive, rural community.
Oh, and to complete the tying up of loose ends, this planet, the one with the lovely farm community of Christmas, is called Trenzalore. if the Doctor wants his people back, it will be at their expense. It’s a siege, and all of the Doctor’s enemies are coming.
The Doctor sends Clara back to the TARDIS on an errand, and as she does so, he sends her back home. She sticks her key in the door as it vanishes. Meanwhile, Tasha Lem instigates a faith change, changing her order’s principal aim to one of silence (very much that sort). So, the Doctor is defending Trenzalore, and the TARDIS is fending Clara off.
The years pass, and pass. Everyone has a go at invading, and everyone fails. Most spectacularly the wooden Cyberman, tricked into shooting himself in the heart.
But all of this excitement is taking its toll on the Doctor, and after 300 years, he’s walking with a cane. But the kids love him. They have punch and judy shows showing him fighting a Monoid. He teaches them to do the waggly-arms dance, and forges a bond with a boy called Barnable.
Then, suddenly, the TARDIS arrives, with a frozen Clara stuck on the front, There’s hugging, and he gives her a tour of his quarters. He shows her the sunrise (and sunset), toasts marshmallows, and explains that he passage of time is wearing him and Handles out. As if to prove a point, Handles dies.
The Doctor explains that he’s at the end of his life. There are 12 regenerations: 13 Doctors. If you factor in the War Doctor and the Metacrisis Doctor (the half-human one that went off with Rose Tyler), he’s at the end of his line. There will be no regeneration. All he can do is fend off the baddies until he can’t fend them off any more.
Time for a quick visit to Tasha (his marshmallow source), who explains that there was a separate chapter of her order called the Kovarians (led by Madame Kovarian, of course), and they attempted to prevent this situation from happening by blowing up the TARDIS. Although ironically their efforts seem to have created the situation as much as they prevented it.
It’s at this point we find out Tasha died at the hands of the invading Daleks, and she develops an eyestalk in her forehead. Now the Daleks know who the Doctor is again, they threaten to kill Clara, to prevent the Doctor from saying his name, but her bravado (and a speech from the Doctor) merely serves to needle the dormant Tasha sufficiently to destroy the Daleks and teleport the Doctor back to Christmas.
It’s no longer a siege, it’s a war. Clara fetches the turkey they were cooking earlier (remember the turkey?) and suddenly discovers she’s been dumped back home again. He’s gone back to Christmas, to end his days fighting off the invaders.
And there are a lot of days to come. Everyone has another go at invading, everyone fails, and eventually there’s just the Daleks, being held at bay by the Doctor and the Silence. For years and years and years.
Back at the same Christmas dinner, in front of the same turkey, a distraught Clara hears the TARDIS once more, and rushes to find it being piloted by Tasha. She has one request, that the Doctor should not die alone. And she takes them back to the war.
A now venerable Doctor awaits her, looking a LOT like his first ever incarnation, They pull a cracker, share a joke, and then it’s time for a final confrontation, the Doctor vs the Daleks, one last time. And all Clara can do is watch.
Except that’s not all she does. She begs the Time Lords for help. And she has plenty of time to do it too, he’s going up the bell tower (and as he points out, the Daleks talk very slowly). Suddenly the crack in the wall seals itself. The Doctor faces off against the Daleks, frail and impertinent, and dying.
But… wait…. a crack has appeared in the night sky, a strange golden glow has arrived, and suddenly the Doctor has fresh breath in his body. Or, as the Daleks put it “THE DOCTOR IS REGENERATING! THE DOCTOR IS REGENERATING!”
And it’s a volcanic display, wiping out the entire Dalek fleet and sending a shockwave through the town. And in the midst of the rubble, a TARDIS. Clara goes inside and finds… the Doctor. Not a new Doctor, not yet, but a reset version of his Eleventh self, looking immaculate. He has time to reflect, time to think over his recent life, and time to cook some fish fingers and custard.
And in his regenerative haze, a moment to think about Amelia Pond, who embodies the changes we all undergo as we grow. right up to the present day, with an adult Amy wishing him a good night as he removes his bow tie.
And then, almost immediately, he’s changed. A new man stands before Clara, with furious eyes, a Scottish accent, and kidneys that don’t match his internal color scheme. As the TARDIS begins to crash, he asks one question:
“Do you happen to know how to fly this thing?”
And with that, we’re off into a brand new future.