A middle-aged author (RICHARD DREYFUSS) learns that a childhood friend was killed trying to break up a fight. The news brings back a flood of memories, most notably those late in the summer of 1959 in the small town of Castle Rock, Oregon. There, the aspiring writer, Gordie Lachance (WIL WHEATON), is one member of a quartet of friends. Following the untimely death of his older brother, Denny (JOHN CUSACK), Gordie has become the invisible kid at home due to his parents still being dazed in their grief.
His best friend is Chris Chambers (RIVER PHOENIX), the most mature and compassionate of the four who's aware of his family's bad reputation and the fact that he'll probably never get out of the town. Then there's Teddy Duchamp (COREY FELDMAN), a somewhat off-kilter kid who's touchy about his mentally unstable father, and the chubby Vern Tessio (JERRY O'CONNELL) who overhears news that will change his and his friends lives forever.
It seems that his older brother, Billy (CASEY SIEMASZKO) and another hoodlum, Charlie Hogan (GARY RILEY), know what happened to Roy Brower, a local kid who's been missing for a while. They've heard he was hit by a train some distance away and Vern dutifully reports this to his friends. Having never seen a dead body and looking for some late summer adventure, the friends agree to set off on foot for the long journey.
Along the way, they discuss a wide variety of topics, from childhood nonsense to family matters and where they -- a bunch of unpopular kids -- fit into the world. As they get closer to finding the body, they must not only deal with the growing gravity of the situation, but also the fact that Billy and his buddies, including Chris' older brother, Eyeball (BRADLEY GREGG) and their leader, Ace Merrill (KIEFER SUTHERLAND), are also on their way to find the body and claim the discovery as theirs.