The forces at work in the modern Holmes boom, which began with the Guy Ritchie films in 2009, the first major adaptation in more than a decade, culminate in two relatively different modernized television shows, Sherlock and Elementary. The consulting detective in the present day gets at a great deal of nuance, and Sherlock in particular in many ways is a study of adaptations as much as of the canon. (The term canon, by the way, traditionally referred to the Bible, but it was in fact first applied to literature with Sherlock Holmes fans and their fan works, in 1911.)
To get at the heart of the appeal, you have to go to the source. The Victorian period saw a dramatic rise in crime, particularly in the British capital, and the invention of the literary detective was a direct response to public fears. Scotland Yard was formed in 1842, and through the establishment of methodical police work, crime rates began to decline. But as the century waned, public anxieties about crime actually rose: the Empire began to spill back onto domestic shores, and xenophobia bred somewhat unfounded fears about the safety of the streets, particularly in the nicer areas of London, far from the concentrated poverty and desolation of the East End. At the same time, rapid leaps in science were busy explaining away the modern world — as Sherlock Holmes came to fruition, many of Conan Doyle’s contemporaries were at work engaging with the ethical complexities of scientific advancement in their fiction, reconciling the romantic with the rational while dealing with growing worries about progress. Holmes hit at an exact convergence of the British public’s anxieties and desires — and he hopped around town solving crime with wit and flair, too.
Sherlock Holmes is a magician who explains his tricks: the deductive leaps that are so easy to parody — “Ah! I can see from the smudge of dirt on your left trouser cuff that your wife is having an affair!” — lie at the heart of the appeal of these stories across all adaptations. We are Watson, or just a bit swifter — we know Holmes’s methods, and revel in watching how they are applied. Holmes is ultra-rational, but the crimes are fanciful. In “Sherlock Holmes, Crime, and the Anxieties of Globalization,” a comprehensive study that situates Holmes perfectly in the time in which he was conceived, Michael Allen Gillespie and John Samuel Harpham cast him as a perfect arbiter of “collective human power”: “Holmes is less an individual than a literary or even mythological representation of the capacities of modern science applied to the discovery of criminal behavior. We can believe in Holmes, in part, because we believe in modern science and its claim that there is an answer to every question and a solution to every problem.”
But then there are the direct modernizations, which began with the Basil Rathbone and Nigel Bruce films in the forties: the filmmakers pulled Holmes and Watson into their own time, fifty years on from the source material. One might argue that the modernization in the new millennium began not with Sherlock but with House, a relatively loose adaptation but still Holmesian at its core. (One might also argue that Holmes has influenced huge swaths of twentieth-century storytelling and modern forensics-based deductive crime solving, on television and elsewhere, but there’s only so much a single essay can handle here.) Moffat and Gatiss cite the Rathbone iteration when they talk about their decision to set Sherlock in modern London. Elementary, set in current-day New York with a female Watson (not the first female Watson, by the way) partly owes a debt to House, a clever, Holmes-influenced procedural that remained, at its heart, a procedural.