Wormwood is the demon nephew who receives letters in C.S. Lewis's The Screwtape Letters.
The book, published in 1942, consists of letters from the senior demon Screwtape to his inexperienced nephew Wormwood. Screwtape gives advice about tempting a human subject, whom the demons call “the Patient.” Lewis presents the advice ironically, allowing readers to examine moral weakness from the viewpoint of the tempter.
The epistolary format makes the book different from a conventional novel. Its fictional demonic bureaucracy is used to discuss pride, distraction, resentment, self-deception, and everyday habits.
Wormwood is not the author of the letters and is not the senior demon giving the instructions. That distinction is central to the premise. The book first appeared during the Second World War and became one of Lewis's most widely read works of Christian apologetics.