In the #1 "New York Times" bestseller "Mindhunter," John Douglas, who headed the FBI's elite Investigative Support Unit, told the story of his brilliant and terrifying career tracking down some of the most heinous criminals in history. Using behavioral profiling and criminal investigative analysis to get into the head and psyche of both the criminal and victim -- to feel what they felt at the critical moment -- Douglas helped crack many high profile cases, including the Trailside Killer, the Atlanta child murders, and the Tylenol murders. Now, working again with his co-author Mark Olshaker, Douglas delves further into the criminal mind with a series of chilling new cases in "Journey into Darkness": Follow the FBI's premier investigative profiler as he penetrates the minds and motives of the most terrifying serial killers. In "Journey into Darkness," Douglas profiles vicious serial killers, rapists, and child molesters. He is straightforward, blunt, often irreverent, and outspoken, but takes pains not to glorify any of these murderers.