Walter Jensen is a famous anthropologist and amateur yachtsman. In 1928, Jensen and his schooner Shara are lost in the Pacific Ocean. Rudy Wells and associates search, to no avail. Jensen with his boat reaches the shield of the Zanans, during an electrical storm. Somehow the storm neutralizes the shield, and he gets through. He lands on the island, badly injured. He is found by the Zanans, who are afraid to go near him.