Time Lords The Master may be the most notorious, but he isn’t the only Time Lord to give the Doctor grief. They are the stately grandfathers of the universe, and this superiority has been known to breed megalomania. The Rani (Kate O'Mara, above, with Anthony Ainley as the Master), for example, experimented on “lower” life forms with a sense of psychotic entitlement in the 80s; the insane and bitter Omega, who debuted in the 1970s, tried to destroy the universe. Meanwhile Rassilon, one of the founding fathers of the Time Lords, sought to end time itself rather than face the destruction of his people in a 2009 episode. With friends like these, who needs enemies?

Photograph: BBC