Teenage Cady Heron was educated in Africa by her scientist parents. When her family moves to the suburbs of Illinois, Cady finally gets to experience public school and gets a quick primer on the cruel, tacit laws of popularity that divide her fellow students into tightly knit cliques. She unwittingly finds herself in the good graces of an elite group of cool students dubbed "the Plastics," but Cady soon realizes how her shallow group of new friends earned this nickname.