Now Jack Batten, well-known for his popular books about the law, has set out to shed light on DNA and other pieces of magic that are regularly worked by scientists and their allies in the forensic field - both at the scenes of crimes and, later, in the laboratories. The route he takes to investigate each piece of forensic science is by way of a particular Canadian trial, and his guides on the route are the detectives, the prosecutors and defence attorneys, and the scientists who actually worked on the cases.