Twice Upon a Time (Doctor Who) The Doctor paraphrases philosopher Bertrand Russell when he advises his future self that "hate is always foolish and love is always wise". Peter Capaldi reprised his role as the Twelfth Doctor. On 30 January 2017, he confirmed that the tenth series would be his last, and that he was set to leave after the 2017 Christmas special. The episode also sees the introduction of Jodie Whittaker as the Thirteenth Doctor, whose casting was announced on 16 July 2017. David Bradley appears in the episode as the First Doctor, having previously portrayed William Hartnell in the docudrama "An Adventure in Space
Dreamland (Doctor Who) and is married to David Tennant who played the tenth Doctor. She portrayed Tanya Webster in the audio drama "Red Dawn" with Davison reprising his role as the Fifth Doctor, and she narrated the Tenth Doctor audio-book "Snowglobe 7". Lisa Bowerman (Saruba Velak) played the Cheetah Person Karra in the 1989 "Doctor Who" serial "Survival" (the last serial of the classic series to be broadcast). Since 1998, she has also played Bernice Summerfield in the ongoing Big Finish audio drama series and in occasional "Doctor Who" audio stories. Veteran actor David Warner has also appeared in numerous Big Finish audio