Gary Webster, Alexander D'Arcy, is a nightclub manager who, with his assistant Georgia, leads a group of women from New York City to dance in his club in Singapore. While flying over the Pacific Ocean, their plane catches fire, splits in half, and plummets into the ocean. The group is next seen a few days later, suffering from dehydration on a life raft, before they finally spot a small island and stagger to dry land.
Having discovered fresh water, they explore the island and come across a cabin. Inside, they discover a dead man caught in a large spider web. According to his journal, the man was a Professor Green researching and mining for uranium, but he feared something terrible was about to happen to him. There's no indication how long the professor planned to be on the island, but the women estimate there is enough food to last them about a month.
That night on the cabin's front porch, Georgia sees Linda Elfie Wagner kiss Gary. Jealous, she pulls Linda away and slaps her. Gary leaves the two women on the porch and ventures out alone where he is bitten by a giant spider and turns into a spider-man beast. He flees into the woods, leaving the women to wonder what has happened to him. The next morning the women search for Gary, leaving only Linda behind in the cabin. Driven by uncontrollable violent urges, Gary kills Linda while she is sitting next to a stream. The remaining women return from their fruitless search for Gary, only to find Linda's dead body.
Twenty-eight days pass, and tensions between the women increase, culminating in a catfight between blondes Babs Barbara Valentin and Nelly Eva Schauland. Gladys Dorothee Parker tries to stop the fight but the brunette is overpowered and forcibly restrained by blonde Kate Helma Vandenberg. Georgia admonishes Babs and Nelly and implores them to stop, but the fight only ends when Gary appears and tries to kill Georgia. The women scream and Gary flees back into the jungle.
Running low on food, the women spot a ship on the horizon. Their hopes appear dashed as they are unable to signal it before it leaves, but two men, Joe Harald Maresch and Bobby Rainer Brandt, disembark from the vessel and arrive in a rowboat with supplies for the professor. Joe and Bobby tell the girls the ship will be returning to pick the men back up, and that they will all be saved as a result. As they wait for the ship's scheduled return, they celebrate their last night on the island with a wild party. Both Gladys and Babs develop an affection for Bobby, leading to a confrontation between the barefoot, bikini-clad brunette and the barefoot, scantily clad blonde. But instead of fighting, Babs tells Gladys that Bobby is only interested in her. Hearing the news, Gladys then heads off to rendezvous with Bobby in the jungle, only to find his dead body, another victim of Gary. Her screams attract the attention of both the other girls as well as Gary who chases her to a clifftop where she falls to her death.
Back at the cabin, Gary attacks Joe and is on the verge of killing him when Georgia Helga Franck strikes Gary with a flaming torch. Gary flees and Joe convinces the girls to grab torches and chase him to a quicksand pond where he drowns. The next morning, the ship arrives and they are rescued.
