Two young boys sneak aboard a spaceship and find themselves whisked away to the mysterious planet Terra. There, they encounter Gamera's old foe Gyaos and two female aliens with a taste for human brains. Gamera must save the children and battle the new monster Guiron, whose entire body is a deadly living weapon.
When a giant stone statue on Wester Island is disturbed, the legendary monster Jiger appears and heads for Japan. Gamera tries to stop this new rival, only to be injured when Jiger lays eggs inside of him. As two boys in a submarine go on a dangerous quest inside of Gamera's body to save him, Jig...
An alien woman from the planet Zigra and her spaceship creates a series of earthquakes around the globe. Two children at a marine park are caught in the crossfire as Gamera must combat the monster Zigra to save the earth.
As a massive alien craft heads to Earth to do evil, three good and powerful superwomen befriend a young boy who has a special connection to Gamera, and old foes return to do battle one more time.