Gilligan's Island - Season 2 - Eps 22: Forward March
The Castaways are frightened as the sounds of battle, including hand grenades and machine guns, rock the island. The culprit turns out to be a gorilla who has found an old WWII weapons cache.
About Gilligan's Island

Title: Gilligan's Island
First Air Date: 1964-09-26
Last Air Date: 1967-04-17
Status: Ended
Rating: 7.431/10 (from 238 votes)
Language: EN
Seasons: 4
Total Episodes: 98
Network: CBS
Genres: Comedy, Family
Production Companies: United Artists Television, CBS, Gladysya Productions
Synopsis
The slapstick adventures of hapless Gilligan, long-suffering Skipper and their gang of mismatched castaways, all stranded on an uncharted desert isle after their tiny ship hit stormy weather.
Cast

Bob Denver
Gilligan

Alan Hale Jr.
Jonas "The Skipper" Grumby

Jim Backus
Thurston Howell, III

Natalie Schafer
Eunice "Lovey" Wentworth Howell

Tina Louise
Ginger Grant

Dawn Wells
Mary Ann Summers

Russell Johnson
Roy "The Professor" Hinkley