In 1985, author Gordie Lachance reads in the newspaper that his childhood best friend, Chris Chambers, has died. Gordie narrates an extended flashback, later revealed to be a story he is writing. The flashback tells of a childhood incident when he, Chris, and two buddies journeyed to find the body of a missing boy near the town of Castle Rock, Oregon during the Labor Day weekend in 1959.
Twelve-year-old Gordie’s parents are too busy grieving the recent death of Gordie’s older brother Denny to pay any attention to Gordie. Gordie’s friends are Chris, Teddy Duchamp, and Vern Tessio. While looking for money that he buried beneath his parents’ porch, Vern overhears his older brother Billy talking with a friend. Recently, Billy and his friend saw the body of a missing boy named Ray Brower outside of town. Billy does not want to report the body because doing so could draw attention to the fact that he and his friend recently stole a car. When Vern tells Gordie, Chris, and Teddy, the four boys – hoping to become local heroes – decide to go looking for the body. After Chris steals his father’s pistol, he and Gordie run into local hoodlum John “Ace” Merrill and Chris’s older brother, Richard “Eyeball” Chambers. Ace threatens Chris with a lit cigarette and steals Gordie’s Yankees cap, which had been a gift from Gordie’s brother.
The four boys begin their journey. After stopping for a drink of water at a junkyard, they get caught trespassing by junkyard owner Milo Pressman and his dog, Chopper. They escape over a fence, and Pressman calls Teddy’s mentally ill father a “loony”; Teddy, enraged, tries to attack him but is restrained by the other boys. The boys continue their hike, and Chris encourages Gordie to fulfill his potential as a writer despite his father’s disapproval. Later, Gordie and Vern are nearly run over by a train while walking across a train bridge, but Gordie saves both their lives by throwing himself and Vern off the bridge at the last second.
That evening, Gordie tells the fictional story of David “Lard-Ass” Hogan, an obese boy who is constantly bullied. Seeking revenge, Lard-Ass enters a pie-eating contest and deliberately vomits, inducing mass vomiting (a “barf-o-rama”) among contestants and the audience. During the night, Chris tells Gordie that he hates being associated with his family’s reputation. Chris admits to Gordie that he stole milk money at school. However, he tells Gordie that he later confessed and returned the money to a teacher. Despite this, Chris was suspended; apparently, the teacher spent the money on herself instead of turning it in to her superiors. Devastated by the teacher’s betrayal, Chris breaks down and cries.
The next day, the boys swim across a swamp and discover that it is filled with leeches. Gordie briefly faints after finding a leech on his groin. After more hiking, the boys locate Ray Brower’s body. The discovery is traumatic for Gordie, who asks Chris why his brother Denny had to die and claims that his father hates him. Chris disagrees, asserting that Gordie’s father simply does not know him well.
Ace and his gang arrive, announce that they are claiming the body, and threaten to beat the four boys if they interfere. When Chris insults Ace and refuses to back down from him, Ace draws a switchblade to kill him. Gordie comes to Chris’s aid by firing a shot into the air with Chris’s father’s gun and then pointing the gun at Ace. Ace demands that Gordie give him the gun, but Gordie refuses, calling Ace a “cheap dime-store hood”. Ace taunts Gordie by asking whether he plans to shoot Ace’s entire gang, and Gordie responds, “No, Ace. Just you.” Ace and his gang depart, vowing revenge.
The four boys, agreeing that it would not be right for anyone to get the credit for finding the body, report it to the authorities via an anonymous phone call. They walk back to Castle Rock and part ways, and the extended flashback ends. The present-day Gordie explains that Chris later went to college and became a lawyer. When attempting to break up a fight in a restaurant, he was stabbed to death. Gordie ends his story with the following words: “I never had any friends later on like the ones I had when I was twelve. Jesus, does anyone?”