"The Return of Doctor Mysterio" is an episode of the British science fiction television series Doctor Who. First broadcast on BBC One on 25 December 2016, it is the twelfth Christmas special since the show's revival in 2005. It was written by Steven Moffat and directed by Ed Bazalgette. The episode received generally positive reviews from critics.

The only episode of 2016, it stars Peter Capaldi as the Twelfth Doctor, and is the first to feature Nardole (Matt Lucas), who was introduced in the previous – Christmas 2015 – episode "The Husbands of River Song", as his companion. The episode is set in New York City, and involves the Doctor and Nardole linking with journalist Lucy Fletcher (Charity Wakefield) and a superhero called The Ghost (Justin Chatwin) to combat brain-swapping aliens.