Twice Upon a Time (Doctor Who) Twice Upon a Time (Doctor Who) "Twice Upon a Time" is an episode of the British science fiction television series "Doctor Who", written by Steven Moffat, directed by Rachel Talalay, and was broadcast as the thirteenth Christmas special on 25 December 2017 on BBC One. It features the final regular appearance of Peter Capaldi as the Twelfth Doctor, the first official appearance of Jodie Whittaker as the Thirteenth Doctor, and guest-stars David Bradley as the First Doctor, having previously portrayed original First Doctor actor William Hartnell in the 2013 docudrama "An Adventure in Space and Time". Pearl Mackie guest stars
The Doctor (Doctor Who) Within the fictional narrative, the Doctor is a Time Lord from the planet Gallifrey who travels through time and space in a dimensionally transcendental – "bigger on the inside" – time machine: the TARDIS (Time And Relative Dimension(s) In Space) which takes the exterior form of a 1963 police telephone call box, and retains the appearance throughout the programme. The Time Lords have dedicated themselves to overseeing all of time and space without interference. The Doctor chose to leave home by stealing an obsolete TARDIS model as revealed in the 1969 serial "The War Games" and depicted in the 2013