The Sherlock Holmes series by Sir Arthur Conan Doyle was hugely influenced by his medical education in Edinburgh, and has provided a template for every mystery written since.
Sherlock Holmes is a private detective who lives in 2 21b Baker Street. The story is told through the eyes of his friend and sometime lodger, Dr John Watson, who writes with as much objectivity as he can muster about the genius exploits of Holmes. His awe of the detective always creeps into the tone, creating a dynamic where the reader becomes as enthralled by Holmes as Watson is.
Yes Holmes is an erratic character. He has low moods, spends days smoking drugs, shoots holes in his living room wall, and reveals his thought processes to Watson with maddening irregularity, making Watson, and the reader run, stumbling, to catch up.
Conan Doyle became tired of Sherlock Holmes long before his readers, and killed the character off in The Reichenbach Falls, where Holmes meets his enemy Moriarty. However, popular demand for Holmes revived the character, and Holmes reveals himself to Watson in disguise in The Hound of the Baskervilles, much to the grief stricken Watson’s astonishment. The two would go on to have many more adventures.
Although Conan Doyle was a prolific writer and produced other adventure series, including the Professor Challenger series which contained The Lost World, Sherlock Holmes eclipsed them all, remaining his best loved work.