[2] An international co-production of Japan and the United States,[3][4] it stars Sonny Chiba, Peggy Neal, Franz Gruber, Andrew Hughes, Tadashi Suganuma, and Hideo Murota.

The story follows reporter Ken Abe and photographer Jenny Gleason as they attend a missile test and stumble upon a mysterious swimming creature with a human silhouette.

The pair is eventually taken to the underwater base of the enigmatic Professor Moore, who has created these fish-men or "water cyborgs."

Moore's plan is shrouded in mystery, but it appears to involve transforming people into fish-people and launching a global war.

Jon Condit of Dread Central rated it two out of five stars, writing "Terror Beneath The Sea is the epitome of a disposable movie.