The strangest part about Tredecim wasn't that thirteen people drowned every year; it was that no one seemed to notice.

When Reece realizes that solving this mystery might land her back in her mother's good graces, she submerges herself in a deadly game where the rules keep changing. But Reese isn't the only one with secrets, and her investigation leads her to believe that her new friends might have more to do with the deaths than she thought. Her only hope of survival is outsmarting the Red-Eyed creature that seemingly has the entire town under its control. But as it turns out, Tredecim is home to more than one killer, and if any of them want to survive, they'll have to discern who the real monsters are.