At an Army fort in Georgia, bordering a forest reserve, are Major Weldon Penderton (MARLON BRANDO) and his wife Leonora (ELIZABETH TAYLOR); their neighbors, Lt. Col. Morris Langdon (BRIAN KEITH), his wife Alison (JULIE HARRIS), and their Filipino houseboy, Anacleto (ZORRO DAVID); and Private Williams (ROBERT FORSTER), assigned to the post stables. One October 1948 morning, Major Penderton summons Private Williams to clean up the lawn of his house at the fort. Leonora is off riding on her stallion, Firebird, accompanied by Colonel Langdon. They romance in the woods. Returning home, Leonora finds Private Williams, who usually cares for her horse, has completed his yard task. She engages him in idle chatter as she writes invitations for an elaborate party she is giving That evening. the Pendertons entertain the Langdons. The atmosphere is strange: Penderton, who has no sexual relationship with his wife, seems to condone the obvious interest of his superior officer. Alison, who suffers through the evening's by-play, has been ill since the death, three years prior, of her malormed baby. Her chief consolation now is the companionship of her effete houseboy, Anacleto, who shares her cultural interests, while disdaining the crudities of her husband. Tonight, they are being observed by Private Williams, hovering in the darkness outside, fascinated by Leonora's attention that afternoon. The next morning, Leonora goes riding, accompanied by both Langdon and her husband. To their amazement, they see Private Williams, stark naked, also riding through the woods. When the Pendertons are asleep that night, in separate bedrooms, Williams returns, squats besides Leonora's bed, staring at her until dawn, then returns to his barracks. When he leaves the house, he is observed by Alison. Alison questions Leonora, next day, when she comes to borrow Anecleto to work at her party that night, but the idea strikes Leonora as being ridiculous. Penderton now decides to prove himself by secretly taking out his wife's horse. Firebird runs away, with Penderfon getting badly scratched by trees in the woods. He beats the horse before dropping with exhaustion. To his horror, Penderfon discovers that he has been observed by Private Williams, sunbathing on a rock. Leonora's party in progress, Penderton returns to the stable, stares, fascinated, at Williams caring for the horse's cuts, before tending to his own wounds. Penderfon returns home with a phony story that causes Leonora to go to the stables to learn the truth. She returns to the party and whips her husband across the face with a riding crop. Alison, meanwhile, is in her sickbed across the way, visited briefly by Captain Weincheck (IRVIN DUGAN), who is being forced into retirement by Penderton, for his lack of "leadership qualities." Unable to sleep, Alison again thinks she sees a figure standing near the Penderton house. Anacleto sits with her, after, and talks about his dreams. In the following days, Penderton's fascination with Williams grows more intense. The Major has difficulfy with his lectures, cutting one short to ride out in search of the sunbathing soldier. After a boxing match, Penderton sfalks the boy, picking up his discarded candy wrapper to add to his secret collection of fetishes, including an antique silver spoon stolen from Captain Weincheck. That night, Alison awakes and from her window sees somebody stealthily enter the Penderton house. She puts on a coat, rushes after the dark figure. Bursting into Penderton's study, she tells him her husband has gone up to Leonora's bedroom. She rushes upstairs, sees Williams instead. Not doubting her, but hoping to avoid a direct confrontation, Penderton eases her back to her own house, where they are greeted by her husband and Anacleto. Alison confronts her husband with the news that his mistress is deceiving him with an enlisted man. With the assistance of Anacleto, she begins packing, planning a separation and divorce. Langdon is convinced that Alison, gone mad, hasn't seen anybody in Leonora's bedroom. The doctors concur and the next day Alison is taken to a sanitarium in Virginia by Langdon and Anacleto. Before Langdon can return to the post, Alison dies of a heart attack and Anacleto vanishes. Langdon and Leonora have difficulty renewing their passion, with Alison dead. They go out to the woods, leaving Penderton to exercise with his barbells. Pressure mounts within Penderton. The strain finally shows on Private Williams, as well. He provokes a fight in the barracks latrine. Unable to control his voyeur instincts any longer, he later gets up from bed, makes his way through a thunderstorm to the Penderton house and Leonora's bedroom. This time, standing by an upstairs window, Penderton sees him. He takes his pistol and shoots the young soldier as he squats by Leonora's sleeping body. The shot startles her awake; Langdon rushes across from his house.