The Doctor Falls the episode, the Doctor (Peter Capaldi) must save himself and the remaining human population of a gigantic colony ship from Mondas, while also dealing with two different incarnations of the Master (Michelle Gomez and John Simm) at once. The episode features a cameo from the First Doctor, now portrayed by David Bradley. He had previously played William Hartnell, the original First Doctor actor, in the 2013 "Doctor Who" docudrama "An Adventure in Space and Time". Aboard the colony ship reversing from the event horizon of a black hole, the Doctor finds Bill has been converted into a Cyberman. The Master
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