'Doctor Who' Christmas finale: What we just learned about Capaldi's epic farewell

Two Doctors don't want to go. Time isn't happy with them. But Bill is back!
 By 
Chris Taylor
 on 
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Original image has been replaced. Credit: Mashable

SAN DIEGO -- The Doctor is refusing to regenerate into what we know to be his upcoming female form, and Time itself is not happy with him.

That's the premise behind "Twice Upon a Time," the official title for Peter Capaldi's final episode of Doctor Who, revealed in an emotional panel at Comic-Con on Sunday that marked a changing of the guard.

And the reason the First Doctor (originally played by William Hartnell, now David Bradley) is showing up at this exact moment, as revealed in the cliffhanger of "The Doctor Falls"? "He's refusing to regenerate too," revealed showrunner Steven Moffat.

In other words, the TARDIS has landed in Antarctica at the very end of Hartnell's last story from 1966, "The Tenth Planet." But it soon moves location to a frozen-in-time World War I battlefield, where Mark Gatiss plays a character known only as The Captain.

And if the idea of two Doctors saying "I don't want to go" at once is giving you the feels, then prepare to collapse in a blubbering wreck -- because Bill Potts (Pearl Mackie) is back, but only for one episode.

The beloved companion, last seen being rescued by her alien girlfriend for a trip across the stars, will return to give the Doctor at least one last hug.

Thirteenth Doctor Jodie Whittaker didn't show up in San Diego to step on Capaldi's farewell, but the outgoing actor revealed he'd recently spoken to her.

"She's so full of excitement and passion about the show," Capaldi said of Whittaker. "It's in great hands."

Moffat was wistful about his own departure from the snow, saying he would miss Comic-Con the most and taking what he called his last opportunity to "faintly annoy 7,000 people at once."

But he was full of outrage at the notion that that there had been any sort of "backlash" against the casting of a female Doctor. Repeating a speech he's delivered to several people at Comic-Con, he insisted that real fans were 100 percent behind her, and wishes "the media would stop writing stories that say otherwise."

For more on that particular theme, check out Moffat and Capaldi's interview with Kevin Smith on Saturday.

Chris Taylor
Chris Taylor

Chris is a veteran tech, entertainment and culture journalist, author of 'How Star Wars Conquered the Universe,' and co-host of the Doctor Who podcast 'Pull to Open.' Hailing from the U.K., Chris got his start as a sub editor on national newspapers. He moved to the U.S. in 1996, and became senior news writer for Time.com a year later. In 2000, he was named San Francisco bureau chief for Time magazine. He has served as senior editor for Business 2.0, and West Coast editor for Fortune Small Business and Fast Company. Chris is a graduate of Merton College, Oxford and the Columbia University Graduate School of Journalism. He is also a long-time volunteer at 826 Valencia, the nationwide after-school program co-founded by author Dave Eggers. His book on the history of Star Wars is an international bestseller and has been translated into 11 languages.

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