A Study in Scarlet

Sir Arthur Conan Doyle's "A Study in Scarlet" houses the debut appearance of the great Sherlock Holmes and his companion Dr. Watson. 
It is the first of the four murder mysteries in the Sherlock Holmes series. "A Study in Scarlet" was first published in 1887 in "Beeton's Christmas Annual" and made into a book the following year.  
 "There's the scarlet thread of murder running through the colorless skein of life, and our duty is to unravel it, and isolate it, and expose every inch of it."