"Crime is common. Logic is rare. Therefore it is upon the logic rather than upon the crime that you should dwell." These words of Sir Arthur Conan Doyle's great detective, recorded by his diligent companion Doctor John Watson in "The Adventure of the Copper Beeches," could be read as advice and warning to the ranks of directors, screenwriters, and actors who would go on to put him, his cases, or some bastardized version of either, on screen. Ever since Sherlock Holmes Baffled (1900), a single-reel motion picture of less than a minute's length which appropriated the character so as to enhance the marvel of its special effects (a disappearing man even the detective could not catch), Holmes has been as much used as adapted by movie makers. Even Basil Rathbone, often cited as the definitive screen Holmes, appeared as the detective in films set in the modern day, in which his Watson—quite at odds with his role in the original stories—was mere bumbling comic relief.

Whether a Young Sherlock Holmes (1985) (Holmes and Watson are plucky proto-Potter schoolboys!) or a Without a Clue (1988) (Watson was the smart one, and Holmes was Michael Caine!), Holmes films have taken liberties with the source material in countless ways: the detective's character changes, or his cases are complicated or invented; his milieu is altered, or his methods sexed up; even logic can go out the window. Holmes is, in short, the closest thing to a King Arthur or a Robin Hood that the modern age has produced. He is, despite a canonical body of accomplished literature, a creature of the popular imagination, endlessly refigured and—key, this—re-energised. This is not to say that all such reinventions are equal—there comes a point at which a director or actor strays so far from the source material that an entirely new character may as well have been invented for the purpose. Respect for—rather than slavishness to—the source is desirable.

Enter Guy Ritchie, a director not noted for his reverence. Ritchie's previous films (for instance, Lock, Stock & Two Smoking Barrels [1998], Snatch [2000], RocknRolla [2008]) were broadly speaking gangster flicks of conspicuously violent trickery, hip and masculine and underscored at their best with a sort of arch, matey wit. He would not have been the first director many would have chosen to take on the cerebral, genteel and, above all, reserved master detective. He had, though, a childhood love of the Conan Doyle stories—or so he claimed in interviews—and that love of "the canon," as Sherlockians like to call the 56 short stories and four novels, would, Ritchie insisted, inform his film. Many were sceptical, particularly when the first trailer was released, featuring women in their underwear, Holmes in the nude, and a good deal of, well, Lock, Stock-like punching and shooting. In particular, the image of Holmes stripped to the waist and standing, bloodied, in a boxing ring surprised many.

The other clear element of that trailer, and here this review reaches the part of the film which qualifies it for inclusion in the reviews section of this esteemed organ, was the supernatural. The villain of the piece, it seemed, would be Lord Blackwood, a shadowy magician who would rise from the dead and warn Holmes in a sepulchral growl that he intended to "twist the very fabric of nature." This, like the boxing ring, was not so counter-intuitive as it first appeared. Conan Doyle was a follower of Edgar Allan Poe in more ways than merely modelling Holmes in part on his predecessor's M. Dupin. Many of his Holmes stories featured the gothic and the supernatural quite heavily. "There is but one step from the grotesque to the horrible," Holmes observed during the adventure of Wisteria Lodge, and many of his cases—from other-worldly hounds on Dartmoor to ravenous vampires in Sussex—should principally be remembered for their interest in the occult, and their success in evoking the reader's dread. The presence of the supernatural—like the physicality of fighting, at which Holmes proves able in stories such as "The Final Problem" or "The Solitary Cyclist"—was no imposition upon the source text.

Ritchie's film is thus suffused with the sort of Victorian gothic genre readers have long grown used to. In the scenes in which Lord Blackwood chants eerily whilst dressed in a long gown and holding a knife above the chest of a virgin, we might even be reminded of the Cthulhu/Sherlock Holmes mash-up of Neil Gaiman's "A Study in Emerald" (2003), or the occult derring-do of Mark Frost's slightly bonkers homage to Conan Doyle in The List of Seven (1993). Beyond Holmes, elements are lifted generously from the contemporary horrors of Sheridan Le Fanu or Bram Stoker (and, yes, Poe), but also the common currency Victoriana which has become so recently popular in horror: before the screening I attended, not coincidentally, Joe Johnston's The Wolfman was trailed. Ritchie mines deeply all of these genre tropes, and if his secret societies, grisly ritual murders, and ominous ravens are not exactly original, they are atmospheric and well executed.

The same could be said of his appropriation of some elements of steampunk. Indeed, at times the film resembles nothing so much as Bryan Talbot's anthropomorphic steampunk graphic novel, Grandville (2009), which feeds off similar influences. At one point, we have revealed to us an advanced clockwork weapon; at another, Holmes unfolds his belt to reveal a number of ingenious-looking gadgets; another scene, in a shipyard, is all grime and chrome, a distinctly unVictorian Victoriana, as influenced by science fiction as by the detective story. One of the final lines of the film has Holmes declare that communicating to a device through the ether will be the future of science; his experiments throughout the movie are emphasised as the work of a man acutely interested in technology and the forging of a sophisticated future, and the prominence in the film of the building of Tower Bridge—though historically dubious—makes the film as interested as any more explicitly steampunk a work in improbable gadgetry as a sort of emblem for progress.

The future is indeed what the story—and its characters—are interested in. On the personal level, Watson—a wonderfully warm performance by Jude Law, who is given in many a reaction shot the duty of communicating emotion to the audience where the more serene Holmes refuses—is looking forward to his marriage to Mary Morstan. The dark urge which drives the plot, however, is Lord Blackwood's urge to shape a future dominated by fear and magic, ruled by awful new alchemies and the powerful men who control them. He hires a scientist—the first of many leads Holmes and Watson follow—to explore and refine compounds and ancient spells and recipes, allowing the film again to mix the arcane with the practical. (Indeed, Blackwood's dark sorcery is known by the members of his order as "practical magic"—we must assume Ritchie was unaware of the 1998 Sandra Bullock and Nicole Kidman vehicle of the same name.) All this will be "beyond what your rational minds comprehends," Blackwood warns Holmes, and this steampunkish tension between real science and flimflam becomes central to the film's theme: that, as Holmes puts it, fear is infectious—and that magic, and even faith (as depicted here by a series of increasingly puritanical religious protestors), have the power to confound and defeat the logical mind.

This brings us back to what I said earlier in this review: that, if a director is to appropriate Holmes, it must be with a view to using his character, rather than merely selling a few extra tickets by recourse to the deerstalker. Holmes is Ritchie's perfect hero in this story. We see him at one point attempting to coax a buzzing swarm of trapped flies into a counter-clockwise synchronised movement; improbably, he achieves this aim by playing a series of particular notes on his violin. "I have succeeded in creating order out of chaos," he tells Watson. This desire is at the core of Sherlock Holmes the character. "Things must be done decently and in order," Conan Doyle has him insist in "The Adventure of the Retired Colourman," and Ritchie and his screenwriters—Michael Robert Johnson, Anthony Peckham, and Simon Kinberg—are alive to this insistence. Faced with Blackwood's confounding sorcery, their Holmes refuses to allow the case to dissolve into mumbo-jumbo and madness. Anyone who has seen the 1939 version of The Hound of the Baskervilles will recognise in Robert Downey Jr.'s performance something of the steadfast certainty of that film's Basil Rathbone, who likewise dismissed the possibility that the supernatural was at work in the world. There is, too, a scene in this film in which Downey Jr.'s Holmes induces himself into a dream state, which is redolent of the Conan Doyle story "The Devil's Foot," in which Holmes says, "I fear that if the matter is beyond humanity it is certainly beyond me." Nothing, ultimately, is beyond Sherlock Holmes, and Ritchie agrees.

The story in this way becomes, quite beyond anyone's expectations, a rather penetrating examination of the power of mysticism on the one hand and logic on the other. That the villain employs the former and the hero the latter probably tells you, dear reader who may not yet have seen the film, all you need to know about where it stands on which is better. It is a theme, of course, with intense contemporary relevance—science in this film, as in our own time, is being challenged by the forces opposed to it.

All this is without mentioning the clever use of Ritchie's trademark slow motion techniques—Holmes thinks so fast that he plans his martial moves in minute detail in the moment before he performs them—and the way in which this at-times absurd film as a whole hangs together with a glorious, yet ominous, good humour. In Downey Jr.'s Holmes—who utters with total conviction direct quotes from the canon ("Data! Data! Data! I can't make bricks without clay!"), and creates a raffish, detached, unpredictable Holmes who can entertain our own age whilst not abandoning the qualities which have seen the character through so many others—Ritchie's grimy, steampunkish melange of a Victorian London, beautifully and viscerally shot throughout, has the hero it sorely needs. So, too, might we.

We've missed you, Sherlock Holmes.

Dan Hartland blogs at http://thestoryandthetruth.wordpress.com.