While covering a test of guided torpedoes, two reporters believe they see what appears to be a strange-looking swimming creature. They investigate the matter further and discover that there is a race of fish-men living under the sea. The fish-men capture the pair and keep them prisoner in their underwater city.
Terror Beneath the Sea is a 1966 science fiction horror film directed by Hajime Sato. An international co-production of Japan and the United States, it stars Sonny Chiba, Peggy Neal, Franz Gruber, Andrew Hughes, Tadashi Suganuma, and Hideo Murota.