The Doctor is a time traveling adventurer of the great and old race known as the Time Lords. A common trait among his species is the ability to regenerate, which means that a Time Lord can survive fatal injuries and heal themselves by regenerating into a new body up to twelve times before running out of regenerations and permanently dying, though it is possible for a brand new cycle of regenerations to be given to any Time Lord.
An illustration of the Doctor's ship, the TARDIS (which takes the form of a blue police box) can be seen in a map of the Blazing World.
The second incarnation of the Doctor appeared in 1969.
What appears to be the First incarnation of the Doctor and his Eleventh incarnation appear and run off shortly before Andrew Norton, another time traveler, shows up.
The Doctor is the titular protagonist from BBC's long running TV-series Doctor Who . Due to copyright reasons, the Doctor is never referenced by name, this possibly explains the slight alterations to two of the Doctor's appearances in their brief cameos. .