Malahide, real name Patrick Gerald Duggan, was born in Berkshire, the son of Irish immigrants, a cook mother and a school secretary father. He was educated at Douai School.

He made his television debut in 1976, in an episode of The Flight of the Heron, then in single episodes of Sutherland's Law and The New Avengers (1976) and ITV Playhouse (1977). He was then in an adaptation of The Eagle of the Ninth, and his first film was Sweeney 2 in the following year.

Since then, he has become a familiar face to screen audiences, often playing villains. His television appearances have included dramas such as Minder (1979-1994), The Singing Detective (1986) and Middlemarch (1994), and he played Ngaio Marsh's Inspector Roderick Alleyn in a 1993-94 series.

His films include Comfort and Joy (1984), A Month in the Country (1987), and Captain Corelli's Mandolin (2001). In 1999 he made a small appearance in the introduction to the James Bond film The World Is Not Enough opposite Pierce Brosnan as a Swiss banker named Lachaise working in Bilbao.

In 2008 he played Mr Ryder in a film of Brideshead Revisited.