Katie Hale should be the perfect scapegoat for murder. She is a 17-year-old girl with severe autism and a complete inability to communicate. But there is a lot more to Katie than most people think, and as her story evolves, we see her go from being the obvious villain, to an apparent victim, and eventually to an unlikely hero.
In the opening chapters it is obvious from her blood splattered clothes, hands, and face that Katie has had some kind of horrific mental breakdown, and has stabbed Sandy, her live-in au pair, to death. But the small town’s deputy chief of police, a strong-willed, intelligent young woman named Marty Price, begins to detect flaws in the “obvious,” and goes from being Katie’s arresting officer to being her staunchest advocate, trying to keep her out of a state mental institution by figuring out who really killed Sandy, and why. But is her allegiance misplaced?
As Marty ties up the loose ends of her investigation to present a nice neat package to the DA showing that Katie could not have committed the murder, she uncovers several pieces of evidence—such as Katie’s fingerprints on the murder weapon—that point directly back at Katie, and she realizes that her first homicide investigation is going to be a lot more complex than she at first imagined. Is Katie being elaborately set up by someone, or did she really do it?
In the course of the investigation, Marty’s all too common misunderstanding of severe autism being a form of mental retardation are corrected not only by Katie’s mother, but also through Marty’s personal and endearing interactions with Katie herself. An entirely different world opens up between the two when Marty discovers that Katie is able to converse by typing through a controversial process known as facilitated communication, and she comes to the humbling realization that not only is Katie not retarded, but that she is in fact an interesting, intelligent, and often clever young lady who just happens to be trapped in a cruelly malfunctioning body.