An Adventure in Space and Time led to him being cast as the First Doctor himself in the 2017 "Doctor Who" episodes "The Doctor Falls" and "Twice Upon a Time" and in a series of audio adventures for Big Finish Productions. In 1966, William Hartnell (David Bradley) is in his dressing room at the BBC. He insults a stagehand who calls him to the set, where the delay caused by his absence is noticed. Hartnell enters in costume, ready to film his last moments as the First Doctor and stands in front of the TARDIS console. Three years earlier, BBC executive Sydney Newman (Brian Cox) is
The Sixth Doctor: The Last Adventure of "Time and the Rani", but due to the firing between seasons of Sixth Doctor actor Colin Baker, the episode gave the event very little screen time and didn't explain what had caused it. Big Finish Productions producer David Richardson approached Baker in 2014, after seeing "The Time of the Doctor", which had depicted (on television) the regeneration of the Eleventh Doctor into the Twelfth: "I felt very strongly that regeneration stories, and each Doctor’s final end, are very important to "Doctor Who" fans – these are stories that allow us to see the Doctor at his most courageous, making