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.
Kōjirō Hongō
Scout Master Mr. Shimida
Tôru Takatsuka
Masao Nakaya
Carl Craig
Jim Morgan
Michiko Yaegaki
Mariko
Peter Williams
Dr. Dobie
Kōji Fujiyama
Self-Defense Force Commander
Mari Atsumi
Junko Aoki
Junko Yashiro
Masako Shibata
