Gamera, the giant prehistoric turtle, sworn to protect the Earth, follows two boys to a hostile planet where brain-eating aliens have taken them prisoner. Gamera battles with Guiron, a giant knife-faced monster, in a struggle to save the kids. The boys discover the aliens' plan to conquer Earth, which compels them to rouse Gamera to a final deadly battle with the space monster.
Attack of the Monsters, originally released as Gamera Tai Daikaiju Giron, has long been a fan favorite and is widely considered the best entry in the series. The schoolboys' bravery, Guiron's fierceness, and Gamera's daring rescue make for a memorable, exciting kaiju film.