''The Dark Knight'' details revealed -- Christopher Nolan debuted six minutes of his new Batman film at ShoWest

Considering all that he and his movie, the Batman Begins sequel The Dark Knight, have been through, director Christopher Nolan isn’t as exhausted as you’d expect. ”I just showed [my first cut] to the studio last Friday,” says the filmmaker during an interview at ShoWest, the movie industry’s annual convention that concluded last week in Las Vegas. ”It’s always pretty nervy, and it was really kind of fun.”

Talk about looking on the bright side. Knight was dealt a tragic blow when costar Heath Ledger died on Jan. 22. By then, his transformation into the ghoulish Joker had piqued fans’ interest. What, they wondered, would Nolan and the studio do? For the director, the answer was simple: work. While the film (out July 18) wrapped last November, sound mixing, visual effects, and other postproduction work remain unfinished. Nolan found that going back day after day and editing countless frames featuring Ledger was what he needed. ”I had something very specific to be getting on with. I felt an enormous responsibility,” he says.

His work was on display at ShoWest, where Nolan unveiled a six-minute scene. The clip, similar to a teaser shown on select screens last December, features a gang in Joker masks robbing a bank. In a fleeting glimpse, Ledger looks fiendishly charming — and thoroughly scary. ”He was very proud of what he’d done,” Nolan says. ”[His interpretation of the Joker is] very much iconic, and very much not [Heath].” Adds star Christian Bale, ”Heath did one hell of a job. I just hope this can celebrate him, celebrate his work.”

Warner Bros. now faces the tricky task of getting moviegoers to share in the celebration. ”We’re proceeding along with what our plans have always been,” says producer Charles Roven. But there’s no mistaking that the tragedy is now, like it or not, associated with the film. Visitors to Knight‘s website are greeted by a memorial for the actor; a black ribbon adorns another official site; and those teaser posters featuring the Joker’s face with the tagline ”Why So Serious?” have been joined by one-sheets featuring an abstract image that’s no longer recognizable as Ledger.

Still, you can’t blame Warner for remaining confident: Batman Begins grossed $372 million worldwide, and Nolan and Co. hope this follow-up will build on its moody story and stylized visuals. ”What we didn’t get to do [in Begins] was show this man who has matured,” says Bale. ”Now it’s somebody who has achieved what he set out to — but is seeing consequences he hadn’t anticipated.” And he thinks Knight leaves the door open: ”Knowing the story, I would like very much to complete a trilogy. It leaves you anticipating something that can get very, very interesting.” — Additional reporting by Nicole Sperling