has announced Matt Smith will hand in his sonic screw driver and Tardis at the end of the year.
Doctor Who marks its 50th anniversary in November with a special episode, which Smith has already filmed.
The BBC said Smith's "spectacular exit" was yet to be revealed and would be "kept tightly under wraps".
Smith first stepped into the Tardis as the 11th Doctor in 2010. Taking over from David Tennant, he was the youngest actor to play the role.
Speaking after the announcement, he said he was "incredibly proud" of what the show had achieved over the last four years under Steven Moffat, the show's lead writer and executive producer.
Smith also thanked fans around the world for their "truly remarkable" dedication to the show.