The Hunt For A Serial Killer: Read An Excerpt From Criminal Profiler John Douglas' New Book StephanieG Tue, 02/01/2022 - 17:44 The Hunt For A Serial Killer: Read An Excerpt From Criminal Profiler John Douglas' New Book Stephanie Gomulka An aspect of true crime hinges on the career of former FBI unit chief and special agent John Douglas. As a criminal profiler with the FBI, he interviewed infamous murderers to create profiles to help identify and stop other unknown active killers in the United States.