The second novel featuring Sherlock Holmes. English original edition- The Sign of the Four (1890), 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. The novel presents the detective's drug habit and humanizes him in a way that had not been done in the preceding novel A Study in Scarlet (1887). Arthur Conan Doyle (1859-1930) was born in Edinburgh and took a degree in medicine at Edinburgh University before becoming a doctor in Southsea. He began writing detective stories to supplement his income and A Study in Scarlet (1887) introduced his finest creation, the hawk-eyed detective, Sherlock Holmes. Il Disoriente - Thriller & Noir A paperback and e-book series published by Intra. Global readability, Italian charm.