In 1974, Archbishop Fulton J. Sheen stated that he intended to write a book about the demonic. But such a book never came to fruition. Now, some fifty years later, Sheen's intended book has finally been compiled, all in his own words.

In On the Demonic, Sheen addresses the history of the demonic, how the devil manifested himself to Our Lord, how he has worked throughout the Church's history, and how the Anti-Christ will come in the end times.

Though Sheen is not optimistic about world history, he is most optimistic about Jesus' final victory: "There is one thing we do know. If Christ wins, we win!"