Mitchell "Mitch" Adams, a de-commissioned U.S. Marine captain who returned from Vietnam a day earlier, wakes up with Kathy, his longtime girl friend, at her apartment. For his official homecoming, they drive to the expensive Minneapolis, Minnesota, home of Mitch's parents, Frank and Mary Adams. Frank, president of Adams Commodities, wants Mitch to join his brokerage firm, but Mitch explains that Vietnam changed his priorities, and now he wants to write a novel about the war. Having already chased Mitch's younger brother, Joey Adams, out of the house for being a conscientious objector, Frank dismisses the idea of his son being a writer, but he thinks Mitch will change his mind when he settles into civilian life. Mitch moves into his former bedroom, but spends most of his time with Kathy and avoids his father. He talks with Kathy about Vietnam and his difficulty getting close to people after seeing friends die. One night, as Mitch and Kathy swim nude in Lake Calhoun, a policeman arrests them for public indecency, and a local newspaper sensationalizes the story because of the prominence of Mitch's family. After a shouting match with Frank, Mitch moves into Kathy's apartment, and brother Joey celebrates by giving Mitch and Kathy a female puppy named Stud. Frank is unhappy with Mitch's new situation, however, and invites his son for lunch at an exclusive country club to offer him a part-time job at the brokerage selling pork bellies. Mitch tells his father he will think about it, but instead goes to a local unemployment office. After learning that no jobs are available, Mitch rides his motorcycle into the hills to clear his mind. He returns to Minneapolis and takes the job at his father's firm. Frank assigns sales chief Guy Murphy to teach Mitch how to make "cold calls" to prospective clients. Frank also gives Mitch a company Porsche, and puts public relations staffer Carol Redding, who comes from a wealthy Minneapolis family, in charge of showing him around. Kathy is unhappy with the new situation, but Mitch assures her that he will continue to write his novel. Over the next few weeks, however, Mitch becomes comfortable with his new status and spends more time with his coworkers, including Carol. When Mitch visits Kathy at the elementary school where she teaches, the difference in their lifestyles seems more evident to him. Finally, after Mitch comes home late, Kathy refuses to speak to him, but he makes up with her at a laundromat. The relationship goes awry, however, when Guy talks Mitch into leasing a sleek new apartment. Mitch tells Kathy he will only use it for writing his novel, but she suspects it will get in the way of his book and their relationship. When Mitch's parents invite Mitch and Kathy to a restaurant to celebrate his birthday and a promotion, Carol stops by their table, and Kathy senses something going on between her and Mitch. Later that night, as Mitch's parents prepare for bed, Mary tells Frank she thinks the promotion will drive Mitch away, rather than bind him to the company. Frank responds by turning off the lights before Mary gets into bed. Mitch tries to write in the new apartment, but there are too many distractions. One night, Carol takes Mitch home from a bar and makes love to him, and days later, Frank tells Mary that maybe their son would be better off with a girl from an important family. Mitch goes to Kathy's school, promises he will quit his job after six months, and asks her to marry him, but she calls him a phony and wishes she had "the old Mitch" back. Mitch packs a few things and rides his motorcycle north to Lake Superior. The proprietor of a gas station and general store tells him there are no cabins in the area, but he might spend the night at an abandoned boat house, and Mitch stays at the shore for a while. One morning, he is awakened by a Native American boy, Billy Whitefoot, who accuses him of trespassing on Indian land. Soon, however, the two become friends. Mitch takes the boy on a motorcycle ride, and Billy shows the visitor his favorite spot in the forest, where deer drink from a stream. At that moment, a hunter fires at a deer and hits Billy in the arm. Mitch rushes him to a hospital, where he meets Billy's grandmother. Learning how dismissively the local whites treat Native Americans and illegally hunt on their land, Mitch decides to spend more time on the shore. He writes a letter of thanks to his father, but explains that he must be free to go his own way; as a postscript, he asks Frank to tell Kathy he loves and misses her. After Frank calls Kathy to his office to read her the letter, she drives north with Stud and finds Mitch on the shore. They embrace.