When five sorority sisters of Theta Pi cause the death of one of their own during a foolish prank gone wrong, they conspire to discard the evidence and never speak of the nightmare again. Fast-forward one year to graduation. As they prepare to say good-bye to the house and each other, the girls plan one last alcohol-fueled bash on Sorority Row, confident their dark secret remains buried. But does it? As the party rages in the front yard, the bedrooms and the hot tub, the girls receive cell phone videos taken the night of Megan’s murder from an anonymous sender who threatens to forward the videos to the police. Then, one by one, the sisters and their unsuspecting boyfriends are stalked by an unseen killer.