Phantom From 10,000 Leagues, The (DVD)

When a scientist tries to create a radioactive death ray, the experiment backfires causing a small turtle to revert to a giant prehistoric size monster. Dr. Ted Stevens (Kent Taylor, The Crawling Hand) meets a government investigators, at the scene of another beach murder caused by this hideous sea monster, while marine biologist Professor King (Michael Whalen, The Dawn Express), who created the monster in his laboratory, is being pursued by a beautiful femme fatale who is blackmailing or killing everyone in sight in an effort to acquire King's top secret files for the Russians.