A mother protects her stepdaughter after the teenager witnesses the murder of her best friend, but is soon forced to come to grips with the terrifying possibility that her stepdaughter may be the real killer.

Thanks to his police officer father's efforts, Shawn Spencer spent his childhood developing a keen eye for detail (and a lasting dislike of his dad). Years later, Shawn's frequent tips to the police lead to him being falsely accused of a crime he solved. Now, Shawn has no choice but to use his abilities to perpetuate his cover story: psychic crime-solving powers, all the while dragging his best friend, his dad, and the police along for the ride.