Which C.S. Lewis book presents Christianity through fictional conversations between a demon and his nephew?

The Screwtape Letters presents Christianity through fictional letters from a demon to his nephew.

Published in book form in 1942, the work consists of correspondence from Screwtape, an experienced tempter, to Wormwood, a younger demon assigned to influence a human being. The letters reverse the expected viewpoint: readers hear strategic advice from Hell while inferring the moral lessons Lewis wants to expose.

Lewis uses satire to examine pride, distraction, self-deception, resentment, and the gradual formation of habits. The human target is usually called “the Patient,” and the divine opponent is referred to indirectly as “the Enemy.”

The book is not a conventional theological treatise or a narrative told from a human hero’s perspective. Its unusual form is the main reason it remains distinctive in Lewis’s bibliography. Lewis later wrote a short piece, “Screwtape Proposes a Toast,” expanding the same satirical framework.