Evil has long fascinated psychologists, philosophers, novelists and playwrights but remains an incredibly difficult concept to talk about. On Evil is a compelling and at times disturbing tour of the many faces of evil. What is evil, and what makes people do awful things? If we can explain evil, do we explain it away? Can we imagine the mind of a serial killer, or does such evil defy description? Does evil depend on a contrast with good, as religion tells us, or can there be evil for evil's sake? Adam Morton argues that any account of evil must help us understand three things: why evil occurs; why evil often arises out of banal or everyday situations; and how we can be seen as evil. Drawing on fascinating examples as diverse as Augustine, Buffy the Vampire Slayer, psychological studies of deviant behaviour and profiles of serial killers, Adam Morton argues that evil occurs when internal, mental barriers against it simply break down. Adam Morton also introduces us to some nightmare people, such as Adolf Eichmann and Hannibal Lecter, reminding us that understanding their actions as humans brings us closer to understanding evil. Exciting and thought-provoking, On Evil is essential reading for anyone interested in a topic that attracts and repels us in equal measure.