Relations are strained between cattle baron Brandt Ruger (Gene Hackman) and his wife, Melissa (Candice Bergen) when he leaves for a two-week hunting trip with some of his wealthy friends.
Mistaking her for a schoolteacher, outlaw Frank Calder (Oliver Reed) and his band of rustlers and thieves kidnap Melissa, not for ransom but because Calder wants to be taught how to read a book.
Traveling by luxurious private train, the hunting party engages in debauchery with women, one of whom Ruger sadistically abuses. Notified that his wife has been taken captive, Ruger arms his friends with high-powered rifles to begin a hunt not for animals but for men.
Calder twice must keep Melissa from being raped by his men. But eventually he overpowers and rapes her himself. Melissa tries to shoot and stab Calder and to flee, each time in vain. She goes on a hunger strike, but cannot resist the temptation of a jar of peaches. She begins to enjoy Calder’s company.
Using rifles with telescopic sights that can allow shooting a target at 800 yards, Ruger and his men begin to pick off the outlaws one by one. Melissa also stabs one, Hog Warren (L. Q. Jones), after he attempts a second time to rape her. Calder charges within close range and is able to shoot one of Ruger’s men. Two others quit the hunting party when they see Ruger’s lack of concern over their friend’s death.
Calder’s men become upset to discover that they have kidnapped such a powerful man’s wife, placing them in danger for no good reason. The men revolt and Calder kills one. When his own best friend, Doc (Mitchell Ryan), is gravely wounded, Calder obeys a last request to put Doc out of his misery.
On his death bed, Hog Warren further angers Ruger by telling him Melissa is now Calder’s woman. In yet another ambush, Ruger sees for himself that Melissa, rather than trying to escape, leaps onto Calder’s horse voluntarily to ride off with him. Ruger’s last remaining ally, Matthew (Simon Oakland), implores him to let her go, but the crazed Ruger pays no mind.
The last of Calder’s men are gunned down from long range at a water hole. Alone now, Calder and Melissa are driven out into the desert. Weak from heat and thirst, their horse dead, they stumble toward an inevitable fate. Ruger materializes on foot. He fatally shoots Calder with his rifle. As Calder is dying Ruger kills Melissa. Ruger then collapses beside them. The credits roll over what appears to be a sepia photograph of three bodies in the sand.