When a decaying Russian satellite crashes on the island, the Professor uses a key component for a barometer. With that device, he learns that a massive wave is going to swamp the island. In desperation, the castaways lash their huts together into one structure in order to have any chance to ride the disaster out.

The Harlem Globetrotters' chartered plane crash lands on the atoll inhabited by the happily marooned Gilligan and fellow castaways, and they all must play basketball against a specially programmed squad of robots controlled by a mad scientist.

In the second of three additional Gilligan's Island movies following the series, the gang finds a way of getting rescued from the "uncharted desert isle" for a second time through a series of misadventures but comes back to turn it into a tropical resort for uptight mainlanders.