War Doctor

An unknown incarnation of the Doctor was encountered by the Eleventh Doctor and Clara Oswald when they entered the Doctor's time stream on Trenzalore.

The Eleventh Doctor, upon coming into contact with this incarnation, spurned the very memory of him. He went so far as to suggest this incarnation did not even hold the moniker of "the Doctor" due to his actions in life. He explained to Clara that his real name was not the point; he chose the name "the Doctor" and explained that the name a person chose was like a promise, and this unknown incarnation was "the one who broke the promise. He is my secret." This unknown incarnation responded by defending those actions, stating he had "no choice" and that he did what he did "in the name of peace and sanity". The Eleventh Doctor acknowledged this to be true, but that it had not been "in the name of the Doctor." (TV: ''The Name of the Doctor)

Behind the scenes

 * Despite the Eleventh Doctor's statement about this incarnation not using the name the Doctor, John Hurt is credited on screen twice -- at the end of the scene and again in the closing credits of the episode -- as "The Doctor".