Story continues below

He would go on to more impressive cinematic cases. Like Hamlet or The Importance of Being Earnest’s Lady Bracknell, playing Holmes quickly became a rite of passage for an actor—and a unique chance to leave a personal stamp on one of fiction’s most immortal characters. Between 1921 and 1923, Eille Norwood, whose performances “amazed” Doyle himself, played the detective no fewer than 47 times (the incomparable Jeremy Brett, who took on the character between 1984 and 1994, is close behind at 41). But the most iconic of the early Sherlock Holmes adaptations are the 14 films (produced from 1939 to 1946) that starred Basil Rathbone as Holmes and the rotund Nigel Bruce as Watson, establishing the popular conception of Watson as a clumsy buffoon.

Watson’s incompetence is just one of the many classic “Sherlock Holmes” tropes that don’t appear in Doyle’s original stories. The great irony of Sherlock Holmes is that, despite a seemingly endless string of adaptations, virtually no one has fully realized Doyle’s original conception of the character. If you pulled a random person out of a crowd and asked them to describe Sherlock Holmes, they’d probably mention a deerstalker hat, or a calabash pipe, or say “Elementary, my dear Watson.” But those popular clichés developed over decades of stage and screen performances.

Story continues below

Please use a JavaScript-enabled device to view this slideshow

Sherlock Holmes is one of those rare literary characters who has far surpassed his creator’s original intentions. Tellingly—and despite his best efforts—Doyle himself couldn’t kill off Sherlock Holmes; though Doyle ended “The Final Problem” by having Holmes fall to his death, he eventually capitulated to fan outcry by having Holmes reappear in two more novels and a number of stories, having “faked his death” all along. There are always more dimensions to Sherlock Holmes, and the character has proven endlessly reinterpretable, earning recent homage from writers like Stephen King and Neil Gaiman.

But fittingly, given the character’s background in acting, Holmes's most recent adventures have come primarily in his many appearances in film and television, which have led to adventures far stranger than anything Doyle could originally have anticipated. In the past five decades, Sherlock Holmes has met Mr. Magoo, faced down Jack the Ripper, been treated by Sigmund Freud, and solved mysteries with Batman and the Teenage Mutant Ninja Turtles. He’s had his role usurped by characters as varied as Daffy Duck, Star Trek: The Next Generation android Data, and an animated mutt called Sherlock Hound. He’s been reimagined for the modern day, as in the BBC’s Sherlock, and reinterpreted, as in TV’s House—which features a brilliant, antisocial medical doctor who lives, not insignificantly, in apartment 221B.

And then there’s Guy Ritchie’s Robert Downey Jr.-starring Sherlock Holmes and its sequel, which is actually one of the detective’s more conventional cinematic outings in decades. If you took everything Sir Arthur Conan Doyle wrote about Sherlock Holmes, put it in a blender, and added a few more fight scenes, the end result would roughly resemble Ritchie’s adaptation. It’s a “greatest hits” of Doyle’s original four novels and 56 short stories: bare-knuckle boxing (The Sign of the Four), Irene Adler (the woman who bested Holmes in “A Scandal in Bohemia”), “the game’s afoot,” (Holmes, quoting Shakespeare’s Henry V, in “The Adventure of the Abbey Grange), and the lingering specter of Professor James Moriarty (“the Napoleon of Crime” first mentioned in “The Final Problem,” who’s played by Jared Harris in Game of Shadows).