His first movie appearance was in 1948 in The Boy With Green Hair. In 1954 his break-out role was one of the singing and dancing brothers -- 'Gideon' -- in the film of the musical Seven Brides for Seven Brothers for which his abilities as a champion gymnast and acrobat were well suited. His further musical roles included the movies Tom Thumb, Hit the Deck and his best know work of his career to which audience members would always remembered him in, West Side Story where he played Riff, the leader of the Jets.

He appeared in the movie Peyton Place in 1957, for which he was nominated for the Academy Award for Best Supporting Actor. In 1962 he appeared in the cinerama movie How the West Was Won. In 1963 he appeared in The Long Ships.

More recently he has appeared in television series such as Nash Bridges, Twin Peaks (in which he played an eccentric psychiatrist), and the Babylon 5 episode A Distant Star in which he played 'Captain Jack Maynard'.

His daughter is Amber Tamblyn with whom he has appeared in "Rebellious" and "Johnny Mysto: Boy Wizard", and in cameo roles in a few episodes of Joan of Arcadia. His brother, Larry Tamblyn, was the drummer with 1960s band The Standells.