Last will and testament

explained to Clara Oswald that the confession dial was, in her terms, the last will and testament of a Time Lord, in this case the Twelfth Doctor. (TV: The Magician's Apprentice)

Behind the scenes
A companion of the Doctor's decided to write out his last will and testament upon learning that a director from Blake's 7 would be joining Dr Who. (NOTVALID: So You Think You'd Make A Good Companion For Dr Who!)