When a broken down Russian satellite crashes on the castaways' island, the Professor uses a key component for a barometer and learns that a massive wave is headed towards their island. In desperation the gang lash their huts together and hope to ride the disaster out. While at sea, Gilligan accidentally starts a fire while cooking and almost burns to floating hut to the water line. While occupied in extinguishing the blaze, they don't notice that the smoke has been spotted by a Navy helicopter that summons a ship to rescue them. Triumphantly they return to Hawaii only to find that the changes have been so great over the years they have trouble fitting in. And just to complicate things even more, two Russian spies want the satellite component that Gilligan is wearing as a necklace.