Santa Claus: The Movie
From Tardis Wiki, the free Doctor Who reference
Santa Claus: The Movie was a film about Santa Claus, which starred Dudley Moore, and also featured Santa's elves. It was a "guilty pleasure" of Shona McCullough, who had rewatched it shortly before being bit by a dream crab and entering a shared dream-state also including the Twelfth Doctor and Clara Oswald. This led to the appearance of Ian the Elf in the dream. (PROSE: Ian the Elf)
Behind the scenes
Judy Cornwell played Anya, the film's interpretation of Mrs Claus. The film also featured Christopher Ryan and Caroline John.