Recording the history of the belief in the existence of Satan, this book draws from the Bible, the poetry of Dante and Milton, the legend of Faust, and from modern novels and plays such as the works of Mark Twain and G.B. Shaw, and the spiritual writing of C. S. Lewis. Fintan Lyons O.S.B. chronicles the decline of that belief through the centuries as well as the attempts to treat the problem of evil philosophically, using the insights of thinkers such as Karl Barth.

At the heart of this book is the attempt to synthesise or reconcile traditional belief with contemporary concern or even alarm regarding evil in the world. Lyons argues that evidence for the persistence of evil has been striking in modern times in wars and atrocities, while phenomena such as Satanic Cults and possible or real diabolical possession have continued to increase. The Catholic Church reacted to this situation in 1998 with a revision of the 1614 Rite of Exorcism, analysed in this book from both theological and psychological standpoints. By arguing that the transition from belief in Satan to personification of evil in historical regimes and characters brings contemporary culture into sharp focus, this book chronicles the history of humanity's attempt to understand the disturbing and mysterious reality of evil.