A mysterious Xilien takes control of Gamera and uses him to destroy Tokyo. The mind-controlled Gamera later arrives on Monster Island, where it fights Zilla, Kumonga, Kamacuras, and (although the fight doesn't exactly end and is very brief) Godzilla. Gamera flies off and starts destroying Chicago. However, Godzilla follows Gamera to continue the fight. As Godzilla gets the upper hand, Gamera is commanded to fly off. At the North Pole, Gamera's commander, a Xilien named Ekrilloss, dissapointed by how Godzilla nearly defeated Gamera, gives Gamera some team mates: Guiron, Destoroyah, Orga, and Gigan. On Monster Island, Godzilla finishes fighting a starfish like creature. Suddenly, Godzilla is attacked by Guiron. Godzilla manages to defeat Guiron, but is ambushed and knocked out by Destoroyah, Orga, and Gigan. At the North Pole, Godzilla has a mind control chip implanted in him bu Ekrilloss. Godzilla and Gamera are sent to attack Osaka. However, the Shobijin awaken Mothra and have her save the world from the two kaiju. After a long battle, Mothra knocks Godzilla and Gamera into a big building, which causes their mind control chips to malfunction. Free from Ekrilloss' control, the two monsters, along with Mothra, go to the North Pole. They attack and eventually destroy Ekrilloss' base, killing Ekrilloss, Destoroyah, Orga, and Gigan in the process. With the world seemingly safe once more, the three monsters leave.
- Unnamed starfish-like kaiju (implied to be called 'Hexaitode')