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 However, the proposal was rejected, and Gatiss was told that there was no available slot or budget. In order to make the film understandable to a general audience, not all personnel involved in the creation of "Doctor Who" are represented. For example, the role of original story editor David Whitaker is merged with that of associate producer Mervyn Pinfield; co-creator Donald Wilson and writer C.E. Webber are also excluded. Part of the production involved the recreation of scenes from the classic series, including missing episodes such as "Marco Polo". Gatiss also had ambitions to recreate the death of Sara Kingdom