Mining engineer Shigeru investigates the disappearance and death of his fellow coworkers when prehistoric nymphs are discovered emerging from the mines. After an attack on the local village, Shigeru heads deeper into the mines only to make a more horrifying discovery in the form a prehistoric flying creature. Soon a second monster appears as the two converge in Fukuoka.

Kenji Sahara
as Shigeru Kawamura

Yumi Shirakawa
as Kiyo

Akihiko Hirata
as Professor Kyuichiro Kashiwagi

Minosuke Yamada
as Mining Chief Osaki

Yoshibumi Tajima
as Izeki

Akio Kobori
as Police Chief Nishimura

Mitsuo Tsuda
as Staff Officer Takeuchi

Ren Imaizumi
as Sunagawa

Jun'ichirō Mukai
as Military officer

Rinsaku Ogata
as Goro