Since the Name of the Doctor concluded the seventh series of the revived Doctor Who, speculation has swamped the Internet as to who John Hurt, introduced as 'The Doctor', actually is within the show. And since the announcement of Peter Capaldi as the 12th Doctor in August 2013, and the release of numerous posters and hints towards the 50th anniversary on November 23rd, it is clear that Hurt plays a mysterious and intriguing role within the show, different to the previous and following Doctors. Numerous theories have been formulated in an attempt to explain, and maybe answer, the question that must never be answered: Doctor Who?
4. A Time War Doctor?
In the Name of the Doctor, the character of 'The Doctor', played by the aforementioned Hurt, appears right at the very end, with Clara claiming not to have seen him in her various encounters with the previous ten incarnations, whilst the Eleventh Doctor claims that he is a secret, or more specifically, 'my secret'. Hurt then gives off a clue as to who he actually is - "What I did I did without choice, in the name of peace and sanity". Now, presuming that this Doctor is either a past or future incarnation, he must have been involved in an important event in the time line of the Doctor - and the first one that springs to mind is the Time War. The Time War has been mentioned numerous times in the revived series, and each mention shows up new places and events like the Fall of Arcadia (Doomsday, 2006), the Nightmare Child (The Stolen Earth, 2008) and even the mention by the Master of running so far, which would imply his involvement in the conflict (Last of the Time Lords, 2007). Presuming that this Doctor is a past incarnation, then he may have been involved in the numerous events that played a part in the war and due to the possible repercussions of these he 'made' himself regenerate - hence the secrecy surrounding his existence and the obvious shame and contempt shown to him by the current Doctor.