is a 1965 science fiction kaiju film directed by Noriaki Yuasa and released by Daiei Film Co., Ltd. The film focuses on Gamera, a giant ancient chelonian creature who terrorizes Japan after it was awakened by an atomic bomb explosion in the Arctic. The film is the first in a series of kaiju (giant monster) films featuring the monster Gamera. Gamera was created by Daiei to capitalize on the success of rival studio Toho's popular Godzilla films, and it, too, spawned its own franchise. It was released in the United States in 1966 as Gammera the Invincible and has been the subject of three different Mystery Science Theater 3000 episodes.