British actor, 1951-present.
Born Peter Moffett and raised in London, Davison had an early role as the Dish of the Day in the TV adaptation of The Hitchhikers Guide to The Galaxy (alongside his then-wife Sandra Dickinson, who was playing Trillian), but his breakout role was as vet Tristan in All Creatures Great and Small, the BBC adaptation of James Herriot's beloved memoirs.
It was this role that brought him to the attention of Doctor Who producer John Nathan-Turner, who was searching for a replacement for outgoing Doctor Tom Baker. Only 29 when he was cast as the Doctor, Davison would be the youngest Doctor until Matt Smith.
Davison played the Doctor's fifth incarnation from 1981 to 1984, following the advice of Patrick Troughton (the actor who played the Second Doctor) to limit his tenure to three seasons to avoid being typecast. Later on, he returned to the role for Big Finish Doctor Who audios and reprised it onscreen in the Children in Need special "Time Crash". His Doctor remains very popular among the fandom, even if he is somewhat overshadowed by his predecessor Tom Baker in the collective consciousness. He initially got a bad rep because of this, although it's worth considering this was where the first hints of problems behind the scenes began to show. But as time has progressed his is considered to have been one of the best Doctors.
Since leaving Doctor Who, he has appeared as a regular in a number of programmes, including A Very Peculiar Practice; Holding The Fort; Campion, for which he also sang the theme tune; The Last Detective; Fear, Stress, and Anger; and Law & Order: UK. He's also made something of a name for himself as a musical theatre actor, with high-profile roles in Spamalot and Legally Blonde: The Musical. Bizarrely enough, composed and performed the theme music to Button Moon. Yes, that's him singing.
His daughter, Georgia Moffett, also acts. She has acted with her father in an episode of The Last Detective, and had a regular role as his on-screen daughter in Fear, Stress, and Anger. She also played his daughter in a different sense on Doctor Who: a female "clone" of sorts made from the Tenth Doctor's DNA. She has a daughter with David Tennant and married him in 2011, so Davison is essentially his own father-in-law.