I just binge-watched some episodes of the television series Forensic Files. The purpose of that long-running series is to show how forensic science has been used to solve murder cases. However, nearly every episode also serves as a documentary about narcissism. Narcissism is an inflated self-esteem that leads people to expect admiration and special treatment. It is one of three bad personality traits (the Dark Triad) that often give rise to bad behaviors, including murder. The other two traits of the Dark Triad are psychopathy (callous disregard for other people’s feelings) and Machiavellianism (a desire to manipulate and control other people).