Terror Beneath the Sea

A Japanese–American co-production from 1966, Terror Beneath the Sea blends science fiction and horror under the direction of Hajime Sato; its Japanese title, Kaitei Daisensō, means 'The Great Undersea War'. Sonny Chiba heads a cast that also includes Peggy Neal, Franz Gruber, Andrew Hughes, Tadashi Suganuma and Hideo Murota, and Shunsuke Kikuchi wrote the score.

Watching a US Navy torpedo test, the reporter Ken Abe and the photographer Jenny Gleason see a mysterious shape rise from the water and set out to learn what it was. Their search leads to a cave of silver fish-men and then to the undersea base of Professor Moore. These "water cyborgs", stripped of their own will, are built as soldiers for the professor's plan to unite the world under his rule, and the film shows in some detail how ordinary people are turned into them. When a US submarine looking for the missing pair and a kidnapped scientist comes upon the base, fighting breaks out, and once the control system fails the cyborgs attack everyone in their way.

The film opened in Japan on 1 July 1966. It had no cinema release in the United States and went straight to television through Teleworld. Reviews outside Japan ran from mixed to negative.