Born in Lincoln, Lincolnshire, the son of a furniture maker (his twin sister died at birth), he was educated at a Quaker school in Reading and briefly attended art college before transferring to the London Academy of Music and Dramatic Art. He graduated in 1972 and went on to work for the Royal National Theatre and the Royal Shakespeare Company as well as acting in Ken Campbell's epic Illuminatus (1976). He also founded the comedy group, the National Theatre of Brent with Patrick Barlow.
He made his film debut in 1978 with a tiny role in Jerzy Skolimowski's The Shout, and made his television debut the following year. He went on to work with Stephen Frears (for television, and in The Hit (1984)) and Terry Gilliam (in Time Bandits (1981) and Brazil (1985)) before establishing himself in Mike Leigh's Life is Sweet (1990). He proved his ability as a character actor in films including Bullets Over Broadway (1994), The Borrowers (1997) and Little Voice (1998) before taking a leading role in another Mike Leigh film, Topsy-Turvy (1999). He built from that role to make a BAFTA winning appearance in Moulin Rouge (2001) and an Oscar-winning one in Iris (2001). Four films featuring him were relased in 2002.
He is best known to television audiences as DCI Roy 'The Slag' Slater in Only Fools and Horses.