Gezora, Ganime, Kameba: Kessen! Nankai no daikaijû is also called as Atom il mostro della galassia, Desafio dos Monstros, Kessen! Nankai no daikaijû, Aliens - Monster des Grauens greifen an, Supesu Amîba, The Space Amoeba, Yog: Monster from Space, Monster des Grauens greifen an。
A space probe is infiltrated by alien beings and then crashes on a remote Pacific atoll. A group planning to build a resort hotel land on the island and discover it to be inhabited by giant mutant monsters created by the aliens in an attempt to conquer the world.