The Asylum is a gothic-style building, isolated in its grounds, where children with psychiatric problems have been admitted and held for treatment. The story is set beneath the Asylum, in a network of tunnels that lead to a chamber called the Depths. Children have been taken to the Depths for decades, if not centuries, where they have been experimented on for a sinister purpose. 16 year-old Finn enters the Asylum. He is intent on reaching the Depths, stopping the experiments done on children, and freeing them. Along the way, Finn meets a girl in the tunnels named Ruth, who helps him whenever he encounters danger. Together, they search for the Depths, in order to stop the psychotic experimenter named Leech, who is aided by his mute Shadows. Along the way, the reader wonders whether Finn is imagining everything he sees, or whether it is Leech tricking him; playing with his mind. There are many twists and turns along the way which keeps the reader guessing to the end.