The Sign of the Four, also called The Sign of Four, is the second novel featuring Sherlock Holmes written by Sir Arthur Conan Doyle. Doyle wrote four novels and 56 short stories featuring the fictional detective.
Sir Arthur Ignatius Conan Doyle KStJ DL was a British writer and medical doctor. He created the character Sherlock Holmes in 1887 when he published A Study in Scarlet, the first of four novels and more than fifty short stories about Holmes and Dr. Watson.