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
An Adventure in Space and Time Who" in 1993, filmmaker Kevin Davies pitched an idea called "The Legend Begins" to the BBC. "The Legend Begins" would have mixed documentary interviews with those responsible for the creation of "Doctor Who" with a dramatised strand showing the programme's beginnings. Eventually, the dramatisation idea was abandoned in favour of a standard documentary format looking at the entire history of "Doctor Who", which was eventually broadcast on BBC1 as "" in November 1993. Ten years later, for the fortieth anniversary, writer and executive producer Mark Gatiss pitched the idea for the film to BBC Four, unaware of Davies's previous attempt.