Fan CastingHow The Monk Got His Habit (2015)

The cold opening of the episode would have begun with the Monk listening to some disco records "one day in his TARDIS". Listening to the song "Ra-Ra-Rasputin" by Boney M, the renegade Time Lord suddenly thinks to himself "how hysterical it would be" to go back to czarist Russia and have the real Grigori Rasputin listen to the song. He does exactly that, only for the experience to drive Rasputin completely mad. This is enough to change history, averting the Russian Revolution of 1917 and consequently mess up the further course of human history. Terrified at what he has done, the Monk phones the Doctor and says: "I've made made a terrible mistake".