2x17 - Most Evil

Gangs. They lure members with promises of respect, money and power. From armed robbery to murder, they are responsible for some of the most brutal crimes. What drives gangsters to kill? Forensic psychiatrist Dr. Michael Stone examines the world's deadliest gangsters, delving into the cases of psychopathic mafia hitman Richard Kuklinski; Paul and Herman Petrillo, who operate a deadly Philadelphia murder ring; Ervil LeBaron, a polygamist Mormon leader who runs his church like the mafia; and Ismael Cisneros, whose affiliation with street gang MS-13 leads him to murder one of his best friends. Dr. Stone speaks face-to-face with Joseph Salcedo, a Los Angeles gangster whose participation in a retaliatory murder landed him behind bars. Using his scale of evil, Dr. Stone analyzes each killer's vicious acts to determine who is most evil.