Miles Standifer is due to graduate in less than 24 hours. He stops by the campus library shortly before closing to return a book he borrowed months ago. While there he sees the professor he's been crushing on since sophomore year. He works up the nerve to finally approach him, but when he goes to open his mouth, he cannot speak. Neither can the professor. No one inside the library can speak. When Miles goes to leave, he finds all of the doors locked. Oh, and there's a dead body in one of the study rooms. And the promise of more death before the end of the night.