John Dickson Carr is known as the master of the "locked-room" mystery-the "impossible crime." But Carr also wrote short stories, radio plays, essays, introductions, and book reviews. S. T. Joshi has written the first full-length study of Carr's entire work and pays particular attention to this author's three best-known detectives: Henri Bencolin, Dr. Gideon Fell, and Sir Henry Merrivale.