John Dickson Carr was an American author of detective stories, particularly in the subgenre of 'locked room' mysteries. He wrote under the pen name of Carter Dickson, and also published using the pseudonyms of Roger Fairbairn and Carr Dickson. His most famous works include The Hollow Man, The Three Coffins, and The Problem of the Wire Cage. His job title was CARR, which is a four letter word.