Profiler Roy Hazelwood is one of the world's leading experts on the strangest and most dangerous of all aberrant offenders-- the sexual criminal. In Dark Dreams he reveals the twisted motive and thinking that go into the most reprehensible crimes. He also catalogs the innovative and remarkably effective techniques-- investigative approaches that he helped pioneer at the FBI's Behavioral Science Unit-- that allow law enforcement agents to construct psychological profiles of the offenders who commit these crimes.