Which C.S. Lewis work presents letters from a demon advising his nephew?

The Screwtape Letters presents letters from a demon advising his nephew.

Published in book form in 1942, the work consists of correspondence from Screwtape, a senior tempter, to his inexperienced nephew Wormwood. Screwtape gives advice about tempting a human referred to only as “the Patient.” Lewis uses this reversed perspective to expose habits such as distraction, vanity, resentment, and self-deception.

The book originated from an idea Lewis had while listening to a wartime speech. He wrote it as a series of letters rather than as a conventional narrative, allowing the advice to become ironic commentary on human behavior. The apparent confidence of the demons is repeatedly undercut by the moral assumptions of the Christian framework.

Lewis dedicated the book to J.R.R. Tolkien, though Tolkien disliked the dedication. The work is often categorized as Christian apologetics, but its epistolary form and satirical voice distinguish it from Lewis’s more direct theological books.