For every sadistic psychopath...there were signs. Charm. Narcissism. Lack of empathy. Impulsiveness. Manipulation. Deception. These traits and others are the telltale . This harrowing half-hour archive series revisits some of the most brutal killers in modern history, reviewing news footage and the words of the killers themselves to see which terrifying traits each killer exhibited. What are the signs...of evil?