It was just a game…until it wasn't. Will Cate discover the assassin before it's too late? Perfect for fans of teen mystery books!TAG. You're It…At Cate's isolated boarding school Killer is more than a game—it's an elite secret society. Members must avoid being "killed" during a series of thrilling pranks—and only the Game Master knows who the "killer" is. When Cate's finally invited to join The Guild of Assassins, she thinks it's her ticket to finally feeling like she belongs