Robert Downey Jr. turns supersleuth in 'Sherlock Holmes'

LONDON -- Robert Downey Jr. is an actor at the top of his game -- already a big-screen superhero, now an iconic supersleuth.

He's also surprisingly open about his self-doubt.

A charismatic performer with a sometimes troubled past, Downey struck box-office gold with the 2008 hit "Iron Man" and now plays the great Victorian detective in Guy Ritchie's action-filled "Sherlock Holmes." He knows he's not many people's mental image of the angular, cerebral and very British Holmes. He hasn't let it stop him.

"You kind of act as if you're up to the task until you find out whether you truly are or not," said Downey, in reflective mood during an interview in London.

"I was fortunate that right about this time last year I was really peaking in my own confidence and faith in my abilities. And seeing as I'd been cast and contracted and it was moving forward, it wasn't like there was any benefit to me not thinking I was the perfect guy for it."

Audiences will soon give their verdict on Downey's muscular, streetwise take on the sleuth of Baker Street. The film had its world premiere Monday in London and opens in the United States on Dec. 25.

Ritchie said Downey was "one of the few American actors" he could imagine as Holmes.

"His English accent is almost flawless. He just seems like the perfect guy." And like Holmes, "his mind works at a speed I can't keep up with."

Downey's detective is not the lanky, languid, deerstalker hat-sporting Holmes of previous screen interpretations. This, after all, is a movie by the director of Cockney gangster-geezer romps "Lock, Stock and Two Smoking Barrels," "Snatch" and "RocknRolla."

When not battling baddies with stick fighting and martial arts, Holmes relaxes with a bit of bare-knuckle boxing. Trusty sidekick Dr. Watson, played by Jude Law, is a wounded Afghan war veteran with a gambling habit and an eye for the ladies.

It's surprisingly faithful to Sir Arthur Conan Doyle's original descriptions of Holmes in stories that began appearing in 1887.

"Oftentimes the innovative thing to do is to be truer to the source material," Downey said.

Downey said he was drawn to Ritchie's take on Holmes as "the first modern martial artist."

"I thought, that's just a fresh way to go."

Conan Doyle fans, who might have feared blasphemy, will find many of the stories' main ingredients present and correct. There's a glimpse of Holmes' criminal nemesis Professor Moriarty, a meaty role for Scotland Yard detective Inspector Lestrade (Eddie Marsan), and a romantic frisson in the form of Irene Adler (Rachel McAdams), the only woman ever to get past the detective's defenses.

At the same time, Downey is the most physical Holmes on film. Ritchie offers up chases, fights and explosions aplenty as Holmes and Watson race to stop an occult conspiracy involving the murderous Lord Blackwood (a menacing Mark Strong) and a secret brotherhood that includes some of Britain's most powerful people.

It's an action romp with a big dose of bromance -- Holmes and Watson spar and bicker like a married couple. Holmes' periods of gloom and his drug habit -- Conan Doyle's hero staves off boredom with a seven-percent solution of cocaine in water -- are only hinted at.

Downey can relate to Holmes. His own career has been marked by restlessness, from the Academy Award-nominated promise of films like "Chaplin" through well-documented drug troubles that saw him do stints of prison, rehab and probation.

Downey says that unlike Holmes, he didn't turn to drugs through boredom.

"That was never really my relationship," he said tersely.

But he acknowledges an affinity with the great detective.

"I don't know that I would be satisfied with anything," he said. "My neutral gear is dissatisfaction. In that way I can really relate to Holmes, because he rebels at stagnation."

Downey's drug and legal troubles ended in 2002, and the last few years have seen a spectacular renaissance. "Iron Man" was followed by a best supporting actor Oscar nomination for "Tropic Thunder" -- a rare awards nod for a broad comedy.

"Iron Man 2" is due for release next year, and it seems inevitable there will be a "Sherlock Holmes" sequel.

Downey said recently that he'd be happy to play Holmes and "Iron Man" hero Tony Stark for the rest of his career -- but that sort of routine seems unlikely.

He says that at 44, his career is finally where he wants it to be.

"I'm in an arena of activity where I get to work with people I would choose to work with, given my druthers," he said. "I think oftentimes before that was the missing component.

"It's a little bit naive on my part, but I always feel like when I'm doing a movie I'm supposed to develop a deep bond with the director so he or she and I can create this third thing, which is the character. And that definitely happened with Guy."