In 1955, Toby Wolff and his mother are on their way to Utah to make their fortune by mining uranium. While in Utah, Toby changes his name to Jack in honor of the author Jack London and also to remove himself from his father, who abandoned Jack and his mother shortly after Jack was born. Jack's father is now living in Connecticut with Jack's brother, Geoffrey, a student at Princeton, and is married to a millionaress.

Jack shares an intimate closeness with his mother who, because of her own abusive childhood, habitually involves herself with violent and volatile men. First, there is Roy, Rosemary's second husband, who follows Rosemary and Jack from Florida to Utah. When Roy leaves them, Rosemary moves with Jack to Seattle, where she meets Dwight, who seems harmless until Jack moves to Chinook to live with him, where Dwight reveals himself to be cruel and petty. Dwight criticizes and berates Jack for real and imagined flaws, and his rants are constantly at the forefront of Jack's mind. Dwight assigns Jack chores for no reason other than to exhibit his power and control over the household. Dwight also forces Jack to deliver newspapers and takes the money Jack earns for himself. The only time Dwight expresses a genuine interest in Jack is when he teaches Jack how to fight. Dwight is excited by Jack's display of aggression, especially because it will be directed against Arthur Gayle, a notorious "sissy" who has a short-lived friendship with Jack.

Jack takes refuge in his unusually vivid, imagination. Dwight's abuse and Jack's own general unhappiness in Chinook only fuel Jack's fantasies. Jack longs to escape from Chinook so that he can recreate himself, but he can only live the life he wants for himself in his own mind. Jack essentially creates his own reality, as is evidenced when he forges ecstatic letters of praise for his application to private boarding schools. In school, Jack tends to run with a dangerous crowd, often getting into trouble with the authorities, but in his applications to private schools, Jack writes that he is an A-student, star athlete, and good citizen. Jack is obsessed with the idea of himself as a virtuous and gifted young man, and has no trouble believing his that lies are the truth.

Jack has many dreams of running away, but he never succeeds in actualizing them. Jack's first real attempt at running away involves a plan to flee to Alaska with Arthur. Jack plans to make his getaway after a Boy Scout meeting in another town, but he ends up befriending a group of boys from another troop, distancing himself from Arthur, and being conned out of all of his money. Later, Jack tries to take refuge with his older brother, Geoffrey, at Princeton, but this plan goes awry when Jack is caught forging a bank check.

Jack finally gets the opportunity to leave Chinook and start anew when he is accepted to the elite Hill School. Mr. Howard, an alumnus of Hill, interviews Jack and serves as Jack's mentor. Later, when Mr. Howard and his wife have Jack fitted for a new wardrobe, Jack is warmed by their attention and affection, which he has experienced very little of at home.

Before Jack leaves home for Hill, he and Rosemary leave Dwight after Dwight shoves Jack in front of her. Rosemary arranges for Jack to live temporarily with his friend Chuck Bolger. Although Jack promises his mother that he will be on his best behavior while at the Bolgers', he breaks his promise and is caught stealing from gasoline from the nearby Welch farm. Jack feels terrible about stealing from the Welches, but cannot bring himself to apologize, which infuriates Mr. Bolger. Mr. Bolger, arranges for Jack to work at the Welch farm, but the Welches refuse Jack's help.

Meanwhile, Chuck Bolger is about to be arrested for the statutory rape of a girl named Tina Flood, who is pregnant, possibly by him. The sheriff offers to excuse Chuck if he to marries Tina, but Chuck refuses. Chuck is on the verge of being sent to jail when he is rescued by another of the defendants, Huff, who agrees to marry Tina in his place.

The summer before Jack is due to begin at Hill, he goes to stay with his father in California to spend some time with his father and his brother. Immediately after Jack arrives, however, his father leaves for Las Vegas with his girlfriend. When Jack's father returns, he is arrested and later committed to a sanitarium, where he remains for the rest of the summer. Not surprisingly, Jack cannot make the grades that Hill demands, and is expelled midway through his senior year. After he is expelled from school, Jack joins the army and serves in the Vietnam War.