Emma Montgomery hasn't been sleeping well. She has gruesome nightmares, and when she wakes up, she isn't where she was when she fell asleep. And she's not the only one. Many of the students at Saint Opportuna High are having nightmares and sleepwalking too. When teenagers start turning up dead, Emma and her friends start to wonder if they might have had anything to do with the deaths. They need to stick together to keep themselves awake...and to figure out what's causing them to kill in their sleep.