What is it that has given the Holmes character such a hold on the public's imagination?
Doyle, as all good writers do, created an evocative, elaborate world that draws the reader in. It is the world of late-Victorian London, with its fogs and its dark, wet streets. Every detail of it is memorable. Holmes' rooms at 221B, for example, are a perfectly cluttered male refuge - comfortable chairs and settees, a desk spilling over with papers, a Persian slipper holding his tobacco, cigars stashed in a coal shuttle, and correspondence stuck to the mantelpiece with a jackknife.
The Holmes character is idiosyncratic and totally fascinating. And his relationship with his friend, Dr. John H. Watson - who is constantly astonished at Holmes' brilliance - is the forerunner of all detective partnerships. (By the way, although the good doctor often asks the detective to explain his deductions, Holmes never actually replies, "Elementary, my dear Watson.")
Doyle had a vibrant imagination. The four novels and 56 short stories starring Holmes, almost all of them narrated by Watson, contain most of what would become the traditions of crime fiction, including clues, dramatic chases, and life-and-death fights.
Doyle also created some of the most memorable villains in all of literature, the most famous of whom was Holmes' archenemy, Professor Moriarty - the Napoleon of crime, the archetype of every supercriminal in literature. There was also Col. Sebastian Moran, "the second-most dangerous man in London" and possessor of a deadly air gun. Irene Adler, the New Jersey-born woman who both charmed and defeated Holmes, was always referred to as "The Woman." And perhaps the most memorable of all of Holmes' cases revolved around the deadly Hound of the Baskervilles.