Despite his overwhelming fear of interacting with people, Christopher, a mathematically-gifted, autistic fifteen-year-old boy, decides to investigate the murder of a neighbor's dog and uncovers secret information about his mother.Christopher decides that he will track down the real killer and turns to his favorite fictional character, the impeccably logical Sherlock Holmes, for inspiration. But the investigation leads him down some unexpected paths and ultimately brings him face to face with the dissolution of his parents' marriage. As he tries to deal with the crisis within his own family, we are drawn into the workings of Christopher's mind