As alien invaders plot to conquer the Earth, two Boy Scouts steal a mini-submarine and discover Gamera in their midst. Transported to the alien's spaceship, the Scouts are menaced by the evil inhabitants, including Viras, a squid-like monster that grows to colossal size to battle Gamera.
Scout Master Mr. Shimida
Masao Nakaya
Jim Morgan
Mariko
Dr. Dobie
Self-Defense Force Commander
Junko Aoki
Masako Shibata
Masao's Father
Jim's Father
Jim’s Mother
Doctor 1
Doctor 2
Doctor 3
Doctor 4
Doctor 5
Boss (voice)
Gamera
