A beautiful con artist (Virginia Mayo) poses as a missionary and travels to an idyllic South Pacific island, where she and two cronies plan to steal a fortune in black pearls guarded by an octopus in an underwater lair. But just as they lay hands on the loot, the natives learn the crooks' true motives and attack. Allan Dwan directs this campy action-thriller that co-stars Dennis Morgan and David Farrar.