"Compelling, essential reading for understanding the underpinnings of psychopathy." -- M. E. Thomas, author of Confessions of a Sociopath For his first fifty-eight years, James Fallon was by all appearances a normal guy. A successful neuroscientist and professor, he'd been raised in a loving family, married his high school sweetheart, and had three kids and lots of friends. Then he learned a shocking truth that would not only disrupt his personal and professional life, but would lead him to question the very nature of his own identity.While researching serial killers, he uncovered a pattern in their brain scans that helped explain their cold and violent behavior. Astonishingly, his own scan matched that pattern. And a few months later he learned that he was descended from a long line of murderers. Fallon set out to reconcile the truth about his own brain with everything he knew as a scientist about the mind, behavior, and personality.