An American actor who first found fame playing pseudo-beatnik (i.e. Hollywood's Middle Americanized bastardization of the Beats) Maynard G. Krebs on the sitcom Dobie Gillis. He's most famous for playing Gilligan on Gilligan's Island.
(Who remembers The Good Guys?). He lives now in West Virginia, IIRC, where he does/did a radio show, and also got arrested for marijuana possession a couple of years ago. Not to be confused with Uncle Duke's nemesis John Denver.