In the bestselling tradition of The Psychopath Test and The Sociopath Next Door, a compelling journey into the science and behavior of psychopaths in our lives, written by the leading scientist in the field of criminal psychopathy. Kent A. Kiehl, who created the Mind Mobil MRI System to study psychopaths in prison populations, has collected the world's largest repository of forensic neuroscience, with scans of more than five hundred psychopaths and three thousand criminal offenders at eight facilities in several states. Kiehl's research has shown that the brains of psychopaths are structurally different from normal brains, offering new clues to how to predict and treat the disease.