Mendes, who won an Academy Award for directing "American Beauty" in 1999, has depicted troubled men with ordinary lives -a far cry from 007, the ultimate action hero.

Bond's playboy image does not reflect the flawed hero in novelist Ian Fleming's books, first published in 1953, Mendes, 46, told a press conference in Istanbul, where "Skyfall" is being shot this month.

"What Fleming created was a very conflicted character," the British filmmaker said. "Some of those things are explored in this movie, because Daniel as an actor is capable of exploring them.

"That was a big thing for me, having a Bond who I believed in, who I felt could take the character to a new level. I could imagine another actor and I wouldn't have wanted to do it."

Craig, 44, reimagined Bond as a dark figure when he took over the role in the franchise's last two films, "Casino Royale" and "Quantum of Solace".

He and Mendes worked closely to develop the story in the latest film. They were afforded extra time to discuss it when production was suspended in 2010 because of financial troubles at MGM, which nearly filed for bankruptcy.

"We were in continued conversation, once Sam agreed to do it," said Craig. "We weren't supposed to talk to each other because MGM hadn't done the deal.

"But we couldn't shut up. It was a chance for us to reread Ian Fleming, and we started emailing each other, 'What about this and what about this?', and that's how it snowballed."

Mendes, 46, said he had long wanted to direct a thriller.

"If I didn't feel I could have made something that was both part of the Bond story and at the same time personal for me, I wouldn't have attempted the movie. I feel like we've found a story that speaks to me," he said.

PLOT KEPT SECRET

While the plot of the 23rd film in Hollywood's longest-running franchise is still a secret, Sony Pictures has said it is about a potential rift between Bond and his boss M, played by Judi Dench, when the past returns to haunt her.

The film has a "very rich" romance, said Craig, 44, and hinted that Bond may reprise the humor that some of his predecessors brought to the role.

"He's funny as hell in this movie," Craig said.

"Skyfall", which also stars Ralph Fiennes as fellow agent Mallory and Javier Bardem as the villain Silva, was shot in Istanbul and the southern Turkish towns of Fethiye and Adana, as well as in Shanghai.

Shooting in Istanbul was a deliberate choice to mark almost 50 years since a Bond film was first set in the ancient city that straddles two continents, said producer Barbara Broccoli, who described Istanbul "as Ian Fleming's favorite city".

"To Russia With Love" with Sean Connery in 1963, included a scene in Istanbul's 6th-Century Basilica Cisterns. The Byzantine-era Leander's Tower on the Bosphorus Strait appeared in "The World is Not Enough" in 1999 with Pierce Brosnan.

"What we've got in store will hopefully combine the best of Istanbul and Turkey without falling into clichés," Mendes said.

"It's an ever-changing, evolving city and we're very much trying to capture the city as it is now, and not as it was 49 years ago."

Earlier this month, a stuntman lost control of his motorcycle and smashed into the window of a 330-year-old shop in the city's historic Grand Bazaar.

"Damage was very minimal," Mendes said. "We've at no stage wanted to harm anything in Istanbul and hope we have been incredibly respectful."

(Editing by Louise Ireland)

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