The fourth child of two Cambridge University professors, Northam was born in Cambridge on December 1, 1961. Following his family's move to Bristol in 1972, he got his first taste of the theatrical world when he took a backstage job at a local playhouse. He went on to study English at London University, but after deciding that acting was his true vocation, left school to pursue his career. Drama studies at the Bristol Old Vic Theatre School, a stint as a singing waiter, and a role in the 1987 TV movie Suspicion followed. In 1989 Northam got his firstalbeit unexpectedbig break when, as an understudy in a production of Hamlet, he took over at the last minute for Daniel Day-Lewis, who suffered a nervous breakdown one night during his performance as the title character.
Receiving positive notices for his impromptu portrayal, the actor found further acclaim the following year with his performance as Edward Voysey in the Royal National Theatre's production of The Voysey Inheritance. Northam won an Olivier Award for Outstanding Newcomer for his work, and, after appearing in 1992's Wuthering Heights and the 1995 Canadian feature Voices, he traveled to Los Angeles, where he landed a leading role in The Net (1995) within five days of his arrival. Playing Jack Devlin, Northam managed to make a mark on audiences as the charismatic villain who tries to off heroine Sandra Bullock while still finding time to sleep with her. Later that year, the actor appeared as a n'er-do-well of a different sort when he played one of Dora Carrington's army of lovers in Carrington. Although his role was essentially limited to a brief maritime seduction of the illustrious lady (played by Emma Thompson), Northam had already landed the considerably more substantial part of Mr. Knightley in Douglas MacGrath's 1996 adaptation of Emma. Starring opposite Gwyneth Paltrow, Northam won both critical praise and the distinction of being that year's thinking woman's luxury import.
The following year, the actor played a supporting role in Steven Spielberg's Amistad, and then went on the same year to explore completely different territory with a turn as Mira Sorvino's husband in the big-budget giant-cockroach thriller Mimic. In 1998, Northam played another married man when he starred as Parker Posey's husband in the romantic comedy The Misadventures of Margaret. He then returned to the world of corsets and BBC English, first as a lawyer in David Mamet's 1999 adaptation of Terence Rattigan's The Winslow Boy, and then as An Ideal Husband in Oliver Parker's adaptation of Oscar Wilde's play. Having gotten the gentrified leading man role down to a science , Northam next went in an entirely different direction as a con man forced to pose as accomplice Steve Zahn's gay lover in a small Texas town in Happy, Texas, which had its premiere at the 1999 Sundance Festival.
-extract from allmovie.com, Rebecca Flint