15. Partners in Crime

How Illinois scientists solved a 1992 murder case involving cremation. It takes a long time and a very hot fire to cremate a human body, and thus destroy all evidence of foul play, but the coroner who performed the autopsy on the badly burned body of Charles "Jack" Lynch found telltale clues. Not only had the victim been burned, he’d also been stabbed -- 24 times, with two different knives. Police knew that a person, acting alone, would probably use only one weapon. So investigators were on the lookout for a couple of killers.