A moon base is destroyed by a spaceship from Zigra which is looking to take over the planet earth to use its oceans for its ocean-dwelling denizens. Gamera must once again come to the aid of the human race while all of Japan roots him on.

The ascetic houseboy of a Japanese lawyer bears witness to the secretive sexual relationship between the lawyer's assistant and the maid, the lawyer's wife's sexual dissatisfaction, and the arrival of the lawyer's brother, who has a plan for the family's land and property.