The Sign of the Four is one of Sir Arthur Conan Doyle's Sherlock Holmes mystery stories. It was the second book to be published and one of the four full length novels. In the story, Sherlock Holmes and the smitten Dr John Watson try to defeat a peg-legged man and his dwarf assistant. It was originally serialised in 'Lippincott's Monthly Magazine' as "The Sign of the Four", but collected in a single volume under the title "The Sign of Four".