Peter Capaldi s magical final chapter as the Twelfth Doctor sees the Time Lord team up with his former self, the First Doctor (David Bradley, Game of Thrones, Harry Potter). Two Doctors stranded in an Arctic snowscape, refusing to face regeneration. Enchanted glass people, stealing their victims from frozen time. And a World War One captain destined to die on the battlefield, but taken from the trenches to play his part in the Doctor s story. Twice Upon A Time is written by Steven Moffat, directed by Rachel Talalay, and executive produced by Brian Minchin. The 60 minute special guest stars Mark Gatiss as The Captain and Nikki Amuka-Bird as the voice of the glass woman, and will see Peter Capaldi s Doctor regenerate into the Thirteenth Doctor (Jodie Whittaker).