Under the Dead Man's Hat — Robert W. Walker

When Dr. Jude Avery teams up with Dr. Sybil Shanley, two medical examiners for Chicago and Cook County, Illinois, they go after the most wanted, savage killers in the city. A team of two violent men known as the Veteran killers graduate to become the Nun killers. The murderers' intent appears on the surface to be to ‘shock and awe' the public. And it is working thanks to the sheer level of extreme depravity and their choice of victims -- easily the most revered and vulnerable in society. Will they graduate to child murder? With one monster in custody, the investigation leads Avery and Shanley to LA, where one of the killers has fled. The entire picture, as to why the killers bludgeoned and filmed their victims' deaths in the age of the internet becomes clearer with each new lead. But each answer is increasingly horrifying. The closer Jude and Sybil get to the truth, the more heinous and gut-wrenching the actual reasoning of the murderers becomes. And as they get closer still to the truth, they must rely more on one another and their weapons, both those on their hips and those in the laboratory.