This teen comedy is the story of 16-year-old Cady Heron (Lindsay Lohan), the home-schooled daughter of zoologist parents. Having spent most of her life in Africa, she is now entering public school for the first time. The social classes are clearly defined at this school near Chicago. The initial culture shock is enormous, but soon Cady begins to learn her way around and is able to get into the school’s most exclusive clique of girls, nicknamed “The Plastics.” When Regina (Rachel McAdams), the most popular girl, discovers that Cady is interested in her ex-boyfriend Aaron Samuels (Jonathan Bennett), things get ugly. Pretending to help Cady, Regina tries to get Aaron back. It becomes a tale of teen vengeance, and things get out of hand when their dirty little deeds become public and the whole school is turned upside down.
Cady is a good girl who becomes corrupted by peer pressure beyond anything she has ever faced. In order to survive, she lowers herself to the horrible tactics of those around her. She finds that she is good at being bad. The humor is sometimes crude and mixed with bad language. In health class, a teacher tries to scare kids by exaggerating the negative effects of sexual activity and then passes out condoms. A woman who has had plastic surgery on her breast is oblivious to a dog chewing on it. Young girls wear revealing outfits, and teachers make out with students. In one disturbing scene, a teen girl lifts her top to a “Girls Gone Wild” video. Due to the bad language, sexual situations, teen partying and crude humor, it does not get the Dove Seal of approval.