Are demons real or figments of our imagination? Should we fear them, or should we pity those who still believe in them? A former Roman Catholic priest examines the role of the devil and demonology in various religions from ancient times to the present day. Years of studying theological literature and the Bible help chart this history. Tracing these ideas offers a fascinating account of who "invented" them and how they developed into their present expressions. These include witchcraft and possession, as well as changing definitions and the evolution of rituals of exorcism-featuring actual case studies.