In the ultimate revenge parable, Carrie is a shy social outcast who has a tough time making friends. A clique of mean girls plan to embarrass Carrie at the upcoming prom by covering her in a bucket full of pig's blood. They fix the balloting so that Carrie and her date are voted prom queen and king, ensuring that she will appear on stage, where they have rigged the bucket.
Just as Carrie accepts her crown, one of the bullies pulls the cord and she is drenched in blood. Carrie snaps and imagines that everyone is laughing at her. With this cruel joke she has reached her breaking point, and the once-demure Carrie wreaks havoc on her peers. She destroys the gym and kills everyone inside using her telekinetic powers.
Carrie is an especially vulnerable victim in her total innocence: early in the film, when she gets her first period during gym class, she doesn't understand what it is. Her tormentors, likewise, have few redeeming characteristics. Bullying, in this instance, is a black-and-white dynamic that can only be righted by the supernatural.