Peter Capaldi's Doctor Who journey – as told by Radio Times covers

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August 2014: The role of a lifetime

“I never thought I’d be in the frame for it because the Doctors were getting younger and younger,” Peter Capaldi told RT in 2014. “Then my agent said, ‘How would you feel about being the new Doctor Who?’ And I just started laughing very joyfully.”

September 2015: A Time Lord’s best friend

“I had no idea who would take over from Matt Smith,” Jenna Coleman told RT. “When I heard it was Peter, it was one of those ‘aha, that makes sense — genius!’ kind of moments. But the first thing he said to me was, ‘There will be no romance in the Tardis.’ ”

Christmas 2015: Daleks unwrapped

“I don’t think there’s any problem with Doctor Who being frightening,” said Peter Capaldi two years ago. “That’s what it’s all about. It’s about introducing children to those emotions and the spice of being scared.” But is he quite scary? “Some mothers have told me that, actually!”

Christmas 2016: Doctor doodles

Capaldi sketched a Dalek on a large piece of perspex, which was later won by one lucky RT reader. The actor said: “The Doctor Who audience covers a huge age range, so you have to entertain the little kids, and hipsters and students, and middle-aged men who should know better.”

April 2017: Educating Bill

“There’s almost an Educating Rita element,” said Capaldi of his latest companion Bill. “The Doctor takes her on as a pupil and there’s a lot of jousting between them.” Pearl Mackie added: “She says things as they are and can be quite direct. He’s surprised by her.” Mackie returns as Bill this Christmas.

December 2017: The Doctor's last adventure

“He’s had enough of becoming other people. He’s having a strop,” said departing showrunner about Capaldi’s Time Lord at the start of this year's Christmas special. “In a wintry landscape he meets the first Doctor, who is also refusing to change. So it’s the 12th Doctor persuading the first to regenerate, and realising he must as well.”

Doctor Who: Twice Upon a Time airs on BBC1 on Christmas Day (Monday 25th December) at 5:30pm