The film opens in a bustling locker room filled with teenage girls, where Carrie White (Sissy Spacek) faces a traumatic moment as she experiences her first period. Panicking and feeling completely alone, she cries out for assistance, but instead of receiving help, her peers cruelly mock her, pelting her with tampons, sanitary towels, and toilet paper. Just as chaos ensues, teacher Miss Collins (Betty Buckley) intervenes to quell the turmoil. Noticing Carrie's intense distress, Miss Collins soon realizes that Carrie is completely unaware of menstruation's basic concept. In response, she requests that the principal excuse Carrie from gym class for a week to help her cope with the shocking experience.
As Carrie makes her way home, she unwittingly harnesses her newfound telekinetic abilities to stop a boy from teasing her. However, her refuge is short-lived; at home, she is tormented by her fanatically religious mother, Margaret (Piper Laurie), who imprisons her in a closet, demanding that she pray for what she believes to be a sinful act. In a fit of rage, Miss Collins later confronts the girls responsible for the torment and forces them into detention, pushing them to their physical limits. The ringleader of the group, Chris Hargensen (Nancy Allen), rebels and ultimately sets her sights on revenge against Carrie when she is banned from the upcoming prom as a consequence of her actions.
Meanwhile, feeling a pang of guilt for her part in the bullying, another girl, Sue Snell (Amy Irving), persuades her boyfriend, Tommy Ross (William Katt), to take Carrie to the prom. Tommy, though reluctant, agrees. When he first asks Carrie to go with him, she denies his invitation, believing it to be another cruel trick. However, after a heartening conversation with Miss Collins, coupled with Tommy’s earnest persistence, Carrie finally relents.
As prom night approaches, Chris, hatching a sinister plot with her boyfriend, Billy Nolan (John Travolta), prepares to exact revenge on Carrie. They slaughter pigs at a nearby farm, capturing their blood in a bucket to enact their cruel scheme during the prom. Seeking her mother's blessing to attend the big night, Carrie faces an unhinged and violent rebuke from Margaret, who fears her daughter will succumb to sin. This escalating conflict sends Carrie into a rage, showcasing her telekinetic powers by violently slamming doors and windows.
On the night of the prom, despite her mother's earlier objections, Carrie and Tommy arrive together and for the first time, she feels a sense of belonging among Tommy's classmates. As the night progresses, Miss Collins relates a poignant story of her own prom, encouraging Carrie to cherish this moment forever. Enveloped in the excitement of acceptance, Carrie and Tommy share a dance, growing closer together—Tommy has genuinely developed feelings for Carrie and seals the moment with a kiss.
However, while the night seems perfect, Chris enacts her revenge. As the prom comes to an exhilarating climax, Carrie and Tommy are elected prom king and queen, leading them to the stage, where Carrie takes in a moment she has longed for. But unbeknownst to her, Chris yanks the cord suspending the bucket of pig's blood, which rains down on Carrie at the worst moment. The crowd reacts in horror, and as Tommy rushes to her aid, he is knocked unconscious by the falling bucket.
> In a twist of tragedy, Carrie erupts in rage, convinced that her peers are laughing at her—a scenario foretold by her mother. In a fit of fury, she unleashes her telekinetic powers, obliterating the gym and claiming the lives of her classmates, including Miss Collins. Following the chaos, a firetruck rushes past Carrie, who faces down Chris and Billy as they attempt to run her over. With a flick of her powers, she destroys the vehicle.
Back home, shaken and overwhelmed, Carrie attempts to cleanse herself in a bath, only to confront her deranged mother. Convinced that Carrie is an evil witch, Margaret attempts to stab her daughter, leading to a fierce struggle where Carrie ultimately uses her abilities to turn the kitchen against her mother, ending her reign of terror. As guilt consumes her, Carrie lights candles and watches her home burn, collapsing around her as she perishes in the flames.
In the aftermath, Sue, one of the few survivors of that fateful night, grapples with her own devastation and guilt over the loss of life. Tormented by nightmares, she finds herself at the site of Carrie's burnt-out home, where, as she lays flowers, a blood-stained hand reaches up from the rubble to claim her. Awaking in terror, she finds herself clutching to her mother for solace, haunted by the horrors of prom night.
