AllMovie

The US Army chooses a supposedly abandoned island as the testing site for "Operation Powder Keg." Naturally, the island chosen is the one where the seven castaways currently reside--and as a result, Gilligan (Bob Denver) and his companions are faced with the disturbing likelihood of being blown to smithereens once the Army begins bombarding them with top-secret missiles. In the end, it is Gilligan who must defuse the only missile that has managed to hit its target...and there isn't much time left before the Big Boom!