Maggie transfers from across town to a new high school that is essentially run by the Silver Daggers, a rough, hierarchical male gang, and their female counterparts, the Dagger Debs. A confrontation between the Dagger Debs and a repo man gets all the female members — and Maggie — arrested. Because Maggie is new, a lecherous lesbian warden at the juvenile detention center threatens to physically abuse her. Maggie fights back and eventually the Dagger Debs join her. Subsequently, Dagger Deb leader Lace decides she likes Maggie and entrusts her with running errands while she serves a brief sentence in juvenile hall. One such errand – delivering a love note to Lace's boyfriend, Dominic – ends in Dominic following Maggie home and raping her. Maggie's close friendship with Lace upsets Lace's closest friend, Patch, who lost one of her eyes in service to the gang and now sees herself as second-in-command.
Lace is released from juvenile hall and reunites with Dominic, telling him that she discovered she was pregnant during her incarceration. Dominic disavows fatherhood and refuses to help Lace care for the child, encouraging her to undergo an abortion. Meanwhile, the Silver Daggers have to contend with the arrival of a new gang, led by the villainous Crabs, at the high school. After Crabs shoots Dominic's brother and orchestrates the gang rape of one of the Debs, Maggie devises an ambush on Crabs's men at a local roller rink. The effort proves disastrous when Crabs's men show up armed with rifles, kill Dominic, and brutally assault Lace, causing her to miscarry. While Lace recuperates in the hospital, Maggie assumes leadership of the gang, expels the men and changes its name to the Jezebels. She teams up with Muff and her gang of African-American militants from across town to ambush Crabs. All the while, Maggie suspects that someone in her group tipped Crabs off to their plans at the roller rink, not knowing that Patch has already uncovered the real traitor: Lace, who organized the ambush to get Maggie killed in revenge for her stealing Dom and for assuming the role of leader of the Dagger Debs. Patch agrees to cover for Lace and, after the ambush proves successful, she shoots Crabs before he can confess to Maggie.
Back at the Jezebels' hideout, Lace and Patch attempt to convince the gang that Maggie was the traitor. The members refuse to believe Lace's assertions, and a knife fight ensues between Lace and Maggie. Maggie fatally stabs Lace in the throat, prompting a police strike force that had been surrounding the building to storm in and arrest everyone. The various members of the gang proudly proclaim themselves as members of the Jezebels, but when Patch attempts to identify herself as part of the gang to the police, the remaining members disavow any knowledge of her. The blood-soaked Maggie becomes hysterical as she and the rest of the gang are loaded into the back of a police van, screaming threats that the Jezebels will one day return.
