A Sheriff is awakened by his daughter, alerting him of a prowler on their ranch. As father and daughter head out into the woods to track the prowler down, they soon discover they're dealing with something that isn't human.

During a Whiton University's pledge week, the carefree partying turns deadly when brutal murders start befalling the students, sending Ellery into a race against time to uncover the truth behind the school's dark secrets and the horrifying meaning of a recurring symbol: a single exclamation mark.