Yōsuke Natsuki

Detective Shindo

Yuriko Hoshi

Naoko Shindo

Hiroshi Koizumi

Professor Murai

Takashi Shimura

Dr. Tsukamoto

Emi Ito

Shobijin

Yumi Ito

Shobijin

Akiko Wakabayashi

Princess Maas Doulina Salno of Selgina

Hisaya Ito

Chief Assassin Malmess

Akihiko Hirata

Chief Detective Okita

Minoru Takada

Prime Minister

Ikio Sawamura

Honest Fisherman

Kōzō Nomura

Geologist

Kenji Sahara

Editor in Chief Kanamaki

Susumu Kurobe

Assassin with Mustache (uncredited)

Tōru Ibuki

Short-Tie Assassin

Kazuo Suzuki

Door-Opener Assassin

Haruya Katō

Journalist

Shin Ōtomo

Boss of Assassins

Senkichi Ōmura

Would-Be Hat Retriever

Yutaka Nakayama

Tourist with Lost Hat

Heihachirō Ōkawa

Astronomer

Hideyo Amamoto

Princess Salno's aide

Yoshio Kosugi

Chief of Infant Island

Yoshibumi Tajima

Ship Captain

Kotaro Tomita

Villager

Yuriko Hanabusa

Mother Shindo

Hideo Shibuya

Journalist

Haruo Nakajima

Godzilla

Shōichi Hirose

King Ghidorah

Katsumi Tezuka

Godzilla (uncredited)