Georgie, a young American woman, stays on a private island in the Caribbean during the time of World War II. Joe is the muscular woman who owns the island, Whale Cay, and she has invited Georgie to stay with her for a time. That evening, a famous actress named Marlene arrives on the island along with a boat full of glamorous people. Georgie is jealous of the beauty of these newcomers, but especially of Marlene, whom it is clear Joe particularly adores. Georgie would rather have all of Joe's romantic affection for herself. At dinner that night with the new guests, Joe talks about one of the native island women named Celia, who is pregnant. Joe and Marlene leave the table together, and eventually Georgie gets up, too, and sits alone in Joe's room, pondering whether or not she can return home now. She is from Sarasota, Florida, where she worked as a mermaid in a local aquarium and lived with her mother and father. She does not want to return to that life.
The next evening, Joe entertains Georgie, Marlene, and Phillip. Phillip is the island's priest, Yale-educated and often drunk. Joe decides to take Georgie and Marlene out on the water, and the three women rip through the water in Joe's boat. Eventually Marlene yells at Joe to stop, and Georgie jumps into the water and swims the mile back to shore. When she returns, she finds Joe in a closet, knives and guns at her feet. Joe shakes and is overcome by her experiences from World War I. At dinner the next night, Phillip urges Joe to put Celia on a boat for the mainland. Celia has been in labor for two days and Phillip believes she is dying. Phillip also warns Joe that the villagers may plan an uprising. Joe listens to nothing he says, and Philip wanders away into the night. Joe won't change her mind when Georgie also urges her to send Celia for medical help. Georgie leaves the house and heads for the island's small church. She finds Phillip and tells him to take the boat and Celia, but Phillip is too drunk. Georgie walks to the edge of the cliffs and dives off, wondering in mid-air if she dove into the wrong place. She barely misses the rocks and floats in the dark water. She stares up at the island where a native woman bleeds.