Cast & Crew
Francis D. Lyon
Scientists aboard the Institute of Modern Science's undersea laboratory enlist the aid of Navy Commander Wayne to identify an underwater moving object detected by their radar instruments. Aboard the laboratory are chief scientist Dr. Le Satier; Sandra, a photographer; and Hugh, a former Navy diver. Friction develops when Wayne accuses Hugh of a cowardly act which caused the deaths of several sailors during his Navy days. Wayne identifies the object as being from outer space when it passes close by the lab. Later, Wayne boards the alien vehicle and returns with a pod-shaped container which, once in the laboratory, begins to expand, eventually erupting to produce a gigantic amphibian monster that destroys the lab's air line connection, leaving only a 12-hour air supply. A monster gains entrance to the lab, killing and injuring some crewmen before returning to its own craft. Hugh sacrifices his life in destroying the spacecraft, thus atoning for his previous act of cowardice by saving the lives of his companions aboard the laboratory.