Fifteen-year-old Will Besting, on the recommendation of his doctor, ends up in Fort Eden, where they help those who suffer from severe fears. Along with six others, he finds himself in this mysterious, abandoned place, where Rainsford - the name of their "brilliant doctor" - must cure them of the worst nightmares of their lives. The treatment works, teenagers feel that they no longer experience fear, but... Every medicine has a side effect. And when the heroes realize that the healing has brought each of them a new disease, Will Besting reveals the darkest secrets of the fort and its inhabitants. What really happened to the seven teenagers trapped in this dark Eden?