A Study in Scarlet is a detective mystery novel written by Sir Arthur Conan Doyle, introducing his new character of Sherlock Holmes, who later became one of the most famous literary detective characters.

Sir Arthur Ignatius Conan Doyle DL (22 May 1859 - 7 July 1930) was a Scottish physician and writer, most noted for his stories about the detective Sherlock Holmes, generally considered a milestone in the field of crime fiction, and for the adventures of Professor Challenger. He was a prolific writer whose other works include science fiction stories, plays, romances, poetry, non-fiction, historical novels and humours. (wikipedia.org)