Guy Ritchie’s Sherlock Holmes is Brokeback Mountain without the sex and depth of emotion, the story of two thrill-seekers who would rather be with each other than just about anywhere else.

Neither acknowledges it explicitly, perhaps because doing so would push Sir Arthur Conan Doyle’s iconic investigators too far down a road Ritchie was reluctant to travel. But between Holmes (Robert Downey Jr.) and Dr. Watson (Jude Law) there exists a bond that supersedes ordinary friendship, an affection conveyed in knowing glances and in the subtext of their droll repartee.

Yet their days together are numbered. Watson is getting married, leaving Holmes to indulge his flights of intellectual curiosity alone, in the cluttered confines of his Baker Street flat. (Brilliance and disorder are natural bedfellows in the great detective’s topsy-turvy universe.) Holmes refuses to accept it. Watson feels most alive when he’s on the case, he argues. Why should a little thing like marriage stand in the way?

Holmes gets his man – being the star of the show, he usually does – and together, he and Watson take down Lord Blackwood (Mark Strong, of Body of Lies), a ritualistic killer with powerful connections inside Scotland Yard. On the eve of his execution, Blackwood reveals his plan to rise from the grave and kill again. Holmes is intrigued but skeptical.

A man of science and logic, Holmes knows Blackwood’s dark magic boils down to so much smoke and mirrors. The challenge before him and the indispensable Watson, who can’t resist the thrill of the hunt, is to prove it. Aiding their pursuit (when it suits her) is the mercurial Irene (Rachel McAdams), with whom Holmes shares an undefined past and an uncertain future.

To this point in his career, Ritchie has made no secret of his obsession with the seedy inner-workings of the London underworld. His appealingly chaotic feature debut, 1998’s Lock, Stock and Two Smoking Barrels, established him as a director with a distinct visual style, yet subsequent efforts have found him going to the same well time and again. His movies have become technical exercises, variations on a formula he helped create.

Holmes finds the director showing off his trademark camerawork – the quick cuts, speeded up to the point of incoherence, never more so than during an especially Ritchian sequence in which Holmes spars at an underground boxing club. The scene lets us know that Holmes is a brawler, as scrappy as he is cerebral, but beyond that, it’s expendable – soft-core eye candy for fans of a shirtless Downey Jr.

The movie works best as a comedy, something Ritchie seems to grasp in fits and starts, though never enough to commit. The ties that bind Holmes to Watson are frequently played for laughs, perhaps to undercut the homoerotic tension, and they remain the most interesting thing Holmes has to offer. Downey Jr. and Law have easy chemistry, and I’d like to see more of it in a better film.

As for the mystery of Blackwood’s return from the grave, the story has no juice. The best Holmes adventures inspire rapt curiosity, but this one, courtesy of Anthony Peckham (Invictus), Simon Kinberg (Mr. & Mrs. Smith) and newcomer Michael Robert Johnson, lacks the drama required.

Casting Downey Jr. in the title role was, as Holmes might say, elementary. He seems to enjoy the character, playing him as a cheeky oddball, with a strangely off-center British accent. If there’s a sequel, and I suspect there will be, I’d like to see him try it again – this time in a movie worthy of the Holmesian canon.