What is the title of C.S. Lewis’s 1950 Christian allegorical novel featuring a demon’s letters?

C.S. Lewis’s 1950 Christian allegorical novel featuring a demon’s letters is The Screwtape Letters.

The book is presented as correspondence from Screwtape, an experienced demon, to his inexperienced nephew Wormwood. Screwtape gives advice about tempting a human referred to only as “the Patient.” Lewis uses this reversed viewpoint to examine pride, distraction, resentment, habit, and spiritual self-deception.

The work began as a series of pieces connected with wartime broadcasting and was published in book form in 1942, with the American edition following in 1943; the commonly cited 1950 date refers to a later publication context and is therefore a potential source of confusion. The title character is not a traditional heroic narrator but an infernal bureaucrat.

The book is often mistaken for a conventional fantasy novel. It is better described as an epistolary Christian apologetic work using satire and allegory.