The following contains ALL THE SPOILERS for Doctor Who‘s 2017 Christmas special, “Twice Upon a Time.” As it’s a regeneration story, we feel trying to review it without spoilers would be antithetical to discussion and analysis. We encourage you to watch the special FIRST before reading the following, or if you’d like to live dangerously, proceed but don’t blame us. Also, if you HAVE watched the special and want a bit of context about Jodie Whittaker’s first scene, click here! And now, Allons-y!

Since the 29th of October, 1966, Doctor Who has been about change, about getting adjusted to the new and the different, generally falling in love with those circumstances, and then gearing up for the inevitable shake-up once again. It’s part of the fabric of the series, and it fills most fans with equal parts sadness and excitement. In the case of “Twice Upon a Time,” regeneration was looming over its existence at all times. It was a fairly somber affair, but one that gave us easily the modern series’ simplest and most self-reflective Christmas specials, all about the end of things, and the beginning of things to come, aided by the once-again masterful direction of Rachel Talalay, one of the standout artists of the Moffat era.

Open an extra present of Christmas content for Twice Upon A Time – quiz, Fact File and more!https://t.co/IOFNPVk9Fv
🎁#DoctorWho pic.twitter.com/fUvU8KNLBV

— Doctor Who (@bbcdoctorwho) December 25, 2017

“Twice Upon a Time” has the distinction that only three previous regeneration stories have – the farewell to both a Doctor and a production team. Patrick Troughton’s regeneration saw the series move to color for the first time; Jon Pertwee’s end moved away from the UNIT family years and back to its universe-hopping exploits, and David Tennant’s bombastic goodbye set fire to the Russell T. Davies years and scorched the ground for the Matt Smith years. With Peter Capaldi’s final bow, we’re also bidding farewell to Steven Moffat as head writer and showrunner, a title he’s held since 2010. Things will be different going forward, and no mistake.

Seeing as Moffat’s given us some of the twistiest, plottiest stories the series has ever gifted the public to unwind, and certainly taking in to account both his last multi-Doctor story (“The Day of the Doctor“) and his last regeneration story (“The Time of the Doctor“), one might expect a thoroughly epic, mind-bending endeavor. But, fittingly and very wisely I think, Moffat eschewed the goofy absurdity and melodrama of RTD’s “The End of Time,” and the puzzling loose-end-tie-up that was “The Time of the Doctor,” and instead gives us quiet, a small cast, a simple message, and a bit of dignity.

As “Twice” opens, we’re treated to scenes from “The Tenth Planet,” 709 episodes ago as the on-screen text informs us. We see William Hartnell and the cloth-faced Cybermen and then we transition into guest star David Bradley’s turn as the First Doctor. Moffat has always played a bit fast and loose with continuity, but he doesn’t futz with it too much, and if you watch that last installment of “The Tenth Planet,” the Doctor does go off on his own to his TARDIS before regenerating.

But he, like the Twelfth Doctor in “The Doctor Falls,” has decided not to regenerate. He’s done. This causes a bit of a time paradox. The First Doctor regenerating is a fixed point in time, as it were, as, perhaps, the Twelfth’s is, so time freezes, going all out of whack, and a World War I captain (Mark Gatiss) who is about to die gets a reprieve and ends up with the Doctors in Antarctica. This is obviously not a great thing, cosmically speaking, and so the mysterious glass-women-robot things attempt to set things right with the timeline.

Unlike previous, planet- (if not universe-) saving regeneration episodes, the Doctors here have already faced their final test. The First Doctor defeated the Cybermen from Mondas and the Twelfth Doctor did likewise; there is no “big bad” to fight this time around. The villain isn’t the Glass Woman (Nikki Amuka-Bird) nor the mainframe of people’s memories, acting nefariously–though the episode does a good job of making us think they must be–it’s the Doctors not doing what they’re meant to do. The Twelfth Doctor even says when he learns the mainframe isn’t evil that he doesn’t know what to do without an evil plan. He’s effectively out of evil plans to face. Nothing to do but face the music.

Bradley’s portrayal of the First Doctor isn’t quite the same mix of sternness and joviality as Hartnell’s but it works well for this special. It’s nice to see the show able to do things like this, and it was a stroke of luck that Gatiss had made that TV movie about William Hartnell and Doctor Who‘s beginnings starring Bradley. Much of the jokes in “Twice” are at how cripplingly old-fashioned the First Doctor is and was. It was the 1960s, and Polly was expected to make tea for the men a lot. It’s upsetting to watch now, and “Twice” tells you that mentality is bad with Capaldi’s every utterance of “You can’t say things like that!”

Moffat bid farewell to his era in a lovely, understated way. He brought back Bill Potts (Pearl Mackie) but didn’t remove her from her happy ending with Heather; instead she’s the sum total of Bill’s memories, and really that IS Bill when you think of it. They were even able to give the Twelfth Doctor back his memories of Clara, which was incredibly sweet, even if Jenna Coleman’s appearance looks like it was filmed on a different planet, let alone a different day. And Matt Lucas coming back for a moment as Nardole was nice as well, just to fully wrap up Capaldi’s time aboard the TARDIS.

There were also quite a few Moffat touches that were much more subtle than I was expecting. We got little nods to fairy tales and the Doctor being one. I never thought we’d see the “Good Dalek” from Capaldi’s second episode “Into the Dalek” again, but it was welcome and worked with the script. Gatiss’ captain being the grandfather of Brigadier Lethbridge-Stewart puts a nice capper on Moffat constantly referencing him, both his death in “The Wedding of River Song” and his zombiefied Cyberman self in “Death in Heaven.” Gatiss’ casting itself was a bit of a nod, he and Moffat co-creating Sherlock and Gatiss being a longtime writer on Doctor Who. And speaking of longtime writers, the German soldier in the standoff with the captain is played by another longtime Who writer, Toby Whithouse. And I may have teared up when we find out it’s the Christmas truce of 1914, indeed one of the most human and humane moments in the history of modern war.

While some will certainly say (and have) that Steven Moffat overstayed his welcome on the series, he did some amazing things for the show, and changed what modern Doctor Who could be, how intricate it was able to become, and how much each season could be different. Peter Capaldi’s farewell was much less about being sad to see a Doctor depart–though it undoubtedly is–but about making your mark, taking your bow, and passing the torch of an institution (and indeed a universal, timeless hero) to a new Doctor, a new showrunner, a new composer, a new style of television, and to a new generation of fans who’ll jump on board, keeping Doctor Who alive for as many regenerations as possible.

As Twelve lets go… Words to hold onto.#DoctorWho pic.twitter.com/YMco9iY9ay

— Doctor Who (@bbcdoctorwho) December 25, 2017

For a full breakdown of Jodie Whittaker’s first scene, click here!

Images: BBC America

Kyle Anderson is the Associate Editor and the resident Whovian for Nerdist. Follow him on Twitter!

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