"SNL" head writer/performer Fey successfully takes her sassy wit to the big screen with this clever teen comedy. Cady (Lohan) is a home-schooled kid raised in Africa attending school for the first time at 16 who uses jungle animals as her frame of reference. The popular girls are The Plastics, Barbie-esque divas led by Regina (McAdams), who take in the brainy Cady for sport. When Cady stupidly reveals her crush on Regina's ex, she quickly becomes a target. Familiar but updated, edgy portrayal of the high school social caste system is probably the smartest teen comedy since the heyday of John Hughes. Based on the non-fiction book "Queen Bees and Wannabees" by Rosalind Wiseman.