Hamlet: Gilligan (Bob Denver)
Ophelia: Ginger (Tina Louise)
Claudius: Mr. Howell (Jim Backus)
Gertrude: Mrs. Howell (Natalie Schafer)
Polonius: The Skipper (Alan Hale)
Laertes: Mary Ann (Dawn Wells)
The Professor (Russell Johnson) is shown to be the Tech Crew (music, light, and curtain duties).
I dare you to watch these songs and not find this entertaining.