Synopsis

A teenage girl, Cady (Lohan), who has been away on safari with her parents, arrives at a new high school in Illinois, where she is accepted into a A-list clique of girriends (McAdams, Chabert, others). When she attracts the interest of the ex-boyfriend (Bennett) of one of her new friends, however, she is marked for punishment by the rules of the clique, which uses practices like nasty gossip, banishment from their lunch table, three-way calling (conversations between two people with a third person seetly listening in), uel Internet messages and "the silent treatment" to get their point aoss. Soon, Cady finds herse using the same tactics in retaliation against her so-called friends...