Which C.S. Lewis book is a fictional correspondence between two demons about tempting a human?

The Screwtape Letters is C.S. Lewis’s fictional correspondence between two demons about tempting a human. The senior demon Screwtape writes instructional letters to his inexperienced nephew, Wormwood.

The book was first published in 1942, initially in installments in the Anglican newspaper The Guardian. Lewis later collected the letters into a volume. Each letter presents advice from a demonic perspective, allowing Lewis to examine pride, distraction, resentment, fear, and self-deception.

The patient being tempted is not named. The demons refer to him as “the Patient,” while God is called “the Enemy” from their viewpoint. This narrative device makes the book satirical rather than a conventional theological treatise.

The Screwtape Letters is often confused with Mere Christianity because both explain Lewis’s Christian ideas to a broad audience. Their forms are different: Mere Christianity develops arguments through nonfiction broadcasts and essays, while The Screwtape Letters uses imaginative correspondence and irony.