In 1976, Fred Wilson, an executive of the Petrox Oil Company, forms an expedition based on infrared imagery which reveals a previously undiscovered Indian Ocean island hidden by a permanent cloud bank. Wilson believes that the island holds vast untapped deposits of oil, a potential fortune which he is determined to secure for Petrox. Unknown to Wilson or the crew, Jack Prescott, a primate Paleontology who wants to see the island for himself, has stowed away on the expedition's vessel, the ''Petrox Explorer''. Prescott reveals himself when he warns the crew that the cloud bank may be caused by some unknown, and potentially dangerous, phenomenon. Wilson orders Prescott locked up, believing him to be a corporate spy from a rival oil company. While being escorted to lock-up, Prescott spots a life raft which, upon inspection, is found to be carrying the beautiful and unconscious Dwan. After conducting a thorough background check on the 'spy', Wilson realizes that he is telling the truth and appoints Prescott as the expedition's official photographer, requesting that, due to his medical training, he be present when Dwan revives. When she does regain consciousness, Dwan states that she is an aspiring actress who was aboard a director's yacht, which suddenly and inexplicably exploded.