A prehistoric monster called Gigantis emerges alongside another creature named Angurus.
小泉博
as Shoichi Tsukioka
Keye Luke
as Shoichi Tsukioka (voice)
若山セツ子
as Hidemi Yamaji
Aya Oyama
as Hidemi Yamaji (voice)
千秋実
as Kôji Kobayashi
Marvin Miller
as Koji Kobayashi / Narrator (voices)
清水将夫
as Dr. Tadokoro
木匠マユリ
as Yasuko Inouye, Koji's girl
笈川武夫
as Osaka Chief of Police
山田巳之助
as Chief of Civil Defense
志村喬
as Doctor Yamane
二代目 澤村宗之助
as Foreman Shibeki
