Who wrote the first Sherlock Holmes novel, 'A Study in Scarlet'?

Arthur Conan Doyle wrote the first Sherlock Holmes novel, A Study in Scarlet.

Published in 1887, the novel introduced both Sherlock Holmes and Dr. John Watson. Watson, recently returned from military service in Afghanistan, becomes Holmes's lodger at 221B Baker Street and records their first case together.

Doyle wrote the book when he was 27, reportedly completing it in about three weeks. It first appeared in Beeton's Christmas Annual before being issued in book form in 1888. The title comes from Holmes's description of murder as a scarlet thread running through ordinary life.

A common mix-up is confusing the novel with The Sign of the Four, which followed in 1890. Doyle ultimately wrote four Holmes novels and 56 Holmes short stories; A Study in Scarlet was the beginning of the original canon.