A nuclear explosion in the far north unleashes Gamera, the legendary flying turtle, from his sleep under the ice. In his search for energy, Gamera wreaks havoc over the entire world, and it's up to the scientists, assisted by a young boy with a strange sympathic link to the monster, to put a stop to Gamera's rampage.
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.
Unusual volcanic activity in Japan awakens Gyaos, a bloodthirsty flying monster with the power to slice things in half with an ultrasonic ray. While scientists and the military scramble to devise a way to stop this new threat, a young boy forms an alliance with Gamera; a monster no one else seems to trust.
