The Doctor 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 the Doctor's very, very good at it.
1996
1985
1974
2022
2007
2003
1966
2001
2023
2021
1992
1999
2006
1963
1988