Coffin made his screen debut in 1973 when he appeared in the television film Much Ado About Nothing, an adaptation of the play, in which he also starred. He appeared in his first feature film in 1976 in the drama Dragonfly, with Beau Bridges and Susan Sarandon. His second feature was the Golden Globe nominated King of the Gypsies, with Shelley Winters. In 1980, Coffin had a leading role in the cult horror classic Mother's Day, his role as the sadistic "Ike" is one he is best known for. Coffin credited himself as Holden McGuire for Mother's Day. During the 1980s, Coffin appeared in several films: the horror film Alone in the Dark, which starred Donald Pleasence, Without a Trace, Nothing Lasts Forever, the biography film Jo Jo Dancer, Your Life Is Calling with Richard Pryor, the action comedy A Fine Mess with Ted Danson, and The Bedroom Window. In the 1990s, Coffin continued to appear in films, one of which he is known for is the comedy film Wayne's World, with Mike Myers and Dana Carvey, and the Steven Seagal film Hard to Kill. He would appear in two final films before his death in 2003: View from the Top with Gwyneth Paltrow, and Identity with John Cusack.