The Doctor looks and seems human. He's handsome, witty, and could be mistaken for just another man in the street. But he is a Time Lord: a 900 year old alien with 2 hearts, part of a gifted civilization who mastered time travel. The Doctor saves planets for a living – more of a hobby actually, and he's very, very good at it. He's saved us from alien menaces and evil from before time began – but just who is he?
The Doctor, from a race called the Time Lords whose home planet is Gallifrey, travels through time and space in his ship the TARDIS (an acronym for Time and Relative Dimensions In Space) with numerous companions. From time to time he regenerates into a new form (which is how the show has been running since 1963).
