Monster from the Ocean Floor

Illustrator Julie Blair is vacationing on the Mexican coast when she learns that there is an unidentified creature in the ocean that has been killing people. One day, while swimming, Julie is startled by a mini, one-person submarine. When she reaches the beach, marine biologist Steve Dunning, who is doing research in the area with Dr. Baldwin of Stanford University, apologizes to Julie for frightening her with his vessel, and then invites her to join them on their boat. On board, Steve and Baldwin show Julie microscopic marine organisms they have discovered. Steve and Baldwin believe that the earth is being exhausted as a source of food and consequently future food supplies will have to come from the oceans. Suddenly, a small fishing boat approaches and a man shouts that his partner, an abalone diver, is trapped underwater. Steve descends into the ocean in his submarine, then, equipped with an air tank, swims to look for the diver, but all he finds is an empty diving suit. Later, Julie tells Steve that the local people are convinced there is some "devil" in the nearby cove. Julie then persuades Steve to follow her in his submarine as she dives, unsuccessfully, to try to find evidence of the monster. When Julie asks Joe, the missing diver's partner, about the monster, he tells her that he has known of its existence since 1946 and suggests that she talk with Pablo, another fisherman. Pablo claims to have seen strange tracks on the beach and adds that one night, during a full moon, a huge mass with one, big red eye stared at him from the ocean then slipped beneath the surface. Tula, a worker at Julie's hotel, tells her that her little dog is missing and that there are strange tracks leading from the beach to the dog's house. During a romantic nighttime walk on the beach, Julie asks Steve if he can explain why the monster was not seen before 1946. When Steve points out that the Bikini underwater experiments took place that year, Julie wonders if perhaps radiation from the experiments might have created the monster. Dr. Baldwin interrupts to tell Steve that their move to another research site has been approved and that they will leave in the morning. After Steve kisses Julie goodbye, he goes to pack, but she stays on the beach. When Julie sees a one-eyed monster break through the surface of the water, she passes out. Meanwhile, Tula convinces Pablo that in order to appease the evil gods who have created the monster, the fairest, Julie, must be sacrificed. To insure Julie's demise, Pablo takes her swimming in a shark filled cove where she fends off a shark with her knife. Pablo then attempts to sabotage Julie's air tank, but this plot also fails. A few days later Steve receives a letter and a package from Julie. The letter explains that while swimming, she ecountered the monster, and tore off bits of its flesh with a grappling hook. When Steve opens the package, he finds a sample of the flesh which he puts in microscope to show to Baldwin. After Baldwin puts canned meat into the object's container and the flesh absorbs it, he deduces that the flesh came from a huge amoeba-like mass and they decide to head back to help Julie. Meanwhile, Pablo attempts to kill Julie with a knife, but cannot go through with it and begs her forgiveness. Julie then dives into the water and locates the monster, a huge, monocular octopus-like creature. Her air supply is low, however, and she soon becomes disoriented and trapped. Upon arriving at the site, Steve immediately dives below in his submarine and rams it into the monster's eye, then escapes through the sub's hatch. Steve finds the nearly unconscious Julie and takes her to the boat, where she recovers and they embrace.