A famous New York aristocrat, Dow Jones Black, has been murdered, and no one knows why. The only living relative of his is his younger sister. They call her Levin. She has four forms of mental illness and has been residing in a mental institution for four years. Stephen Carter, fresh to the field of psychiatry in the FBI, must unlock the mystery of the killer through the help of Levin. Travel through Levin's complicated brain and the effects of mental illness while she and Detective Carter find the killer.