A Study in Scarlet: A Sherlock Holmes Adventure. Артур Конан Дойл

After a harrowing military tour of Afghanistan, Dr. Watson returns to London to convalesce at 221B Baker Street, home to the enigmatic Sherlock Holmes. Their lives are irrevocably thrown together by news that a man has been found dead in a grimy "ill-omened" house, with the word rache -German for "revenge"- written in blood on the wall. This grisly discovery is complicated further by the look of utter horror on the victim's face, and the complete absence of any wounds on the body or sign of a struggle.

First published in 1887, A Study in Scarlet is the remarkable first outing of one of literature's most famous partnerships.