During the 1930s at Oxford, C. S. Lewis, J. R. R. Tolkien, and Charles Williams-remarkable friends, writers, and scholars-met regularly to discuss philosophy and literature and to read aloud from their own works in progress. Calling themselves the Inklings, their circle grew. It was in this company that such classics as The Lord of the Rings, The Screwtape Letters, and The Lion, the Witch, and the Wardrobe first found an audience. Author Humphrey...