The idea for "The Night of the Doctor" came following the creation of the previous unknown incarnation of The Doctor played by John Hurt in The Name of the Doctor (2013). Steven Moffat decided that he wanted to see how this Doctor came into being, with the best story idea being a direct regeneration from the Eighth Doctor, which would have added benefit of showing the end of the Eighth Doctor, which Moffat always wanted to see. Having contacted Paul McGann, who indicated his willingness to participate, Moffat then constructed the mini-episode to serve as an additional surprise for the fans, as well as serving as an introductory piece to The Day of the Doctor (2013).
Paul McGann returns as the Eighth Doctor, 17 years after his only other on-screen appearance in Doctor Who: The Movie (1996).
The first appearance of the planet Karn and the Sisterhood of the Flame since The Brain of Morbius: Part Four (1976), the end of their first appearance.
Pictures of this minisode were leaked, so the BBC had to release the episode earlier. The episode was released on Paul McGann's 51st birthday. McGann jokingly claims that it is Steven Moffat's present for his birthday.