James Gilmore Backus (February 25, 1913 – July 3, 1989) was an American actor. Among his most famous roles were Thurston Howell III on the 1960s sitcom Gilligan's Island, the father of James Dean's character in Rebel Without a Cause, the voice of the near-sighted cartoon character Mr. Magoo, the rich Hubert Updike III on the radio version of The...