Hopper appeared on Broadway and won a contract at Paramount Pictures. He played the leading many in the movies Public Wedding and Over the Goal and starred in the films The Footloose Heiress and Mystery House. After returning to acting from the military he went on to star in a number of films including The High and the Mighty, Rebel Without a Cause, The Bad Seed, and more. In 1959 he was nominated for a Primetime Emmy Award for Best Supporting Actor (Continuing Character) in a Dramatic Series for Perry Mason. William Hopper passed away on March 6, 1970 at 55 years old of a stroke.