A group of six sorority sisters – Kelli (Katie Cassidy), Dana (Lacey Chabert), Lauren (Crystal Lowe), Megan (Jessica Harmon), Heather (Mary Elizabeth Winstead) and Melissa (Michelle Trachtenberg) and their house mother (Andrea Martin) are settling in for Christmas Break. Their seasonal serenity and good cheer is defiled by unsettling and threatening phone calls. Then, one of their own goes missing and the girls are soon being slaughtered one by one.