Rescue from Gilligan's Island

The name of this movie is Rescue from Gilligan's Island released in 1978-10-21 and it's main theme is 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..