Deanie Loomis, a teen-aged girl living in a small town in Kansas in 1928, follows her mother's advice to resist her desire for sex with her boyfriend, Bud Stamper, the scion of the most prosperous family in town. In his turn, Bud reluctantly follows the advice of his father, who suggests that he find another kind of girl with whom to satisfy his sexual desires.
Bud's parents are disappointed by, and ashamed of, his older sister—she is sexually promiscuous, smokes, drinks, and has had an abortion—and accordingly 'pin all their hopes' on Bud.
As the story progresses, Deanie is driven close to madness and institutionalized. Bud's family loses its fortune in the Great Depression, which leads to the father's suicide; and Bud takes up farming, which he had postponed because of his father's aspirations for him.
In the final scene, Deanie, home from the sanitorium after two and a half years, goes to meet Bud. He is now married to the daughter of Italian immigrants; he and his wife, whom he met while complying with his father's desire that he attend Yale University, have an infant child. After their brief reunion, Deanie and Bud see that they must continue their lives separately.