The planet Anthea and his humanoid inhabitants are succumbing to a terrible drought. One the few survivors decides to reach the Earth to find a way to save his planet and his people. On the Earth, he takes the name of Thomas Jerome Newton (David Bowie) and disguises himself as human. Thanks to his superior technical knowledge, Newton deposits a number of ground-breaking patents, like an innovative camera film. The World Enterprises Corporation, his winning technology-based conglomerate, makes him enormously rich and Newton plans to reinvest this wealth in the construction of a space vehicle capable of change the fate of his planet. He hires the scientist Nathan Bryce (Rip Torn) to this effect, and he becomes one of Newton's few friend. The peculiar relationship of the working class girl Mary-Lou (Candy Clark) with Newton, his insane appetite for alcohol and the CIA's curiosity, will be some the snags along the way that may lead to Anthea salvation.