Murder 42 was the title of the homemade video that shocked Scottsdale detectives and special agents of the Federal Bureau of Investigation. The killer on the video never reveals his face, and with few leads, the FBI doesn't believe they will ever find him. The video falls into the lap of Special Agent Gio Adami, now an Assistant Special Agent in Charge in the prestigious Behavioral Science Unit, and he turns to the one person he knows can help him:...