Batman TDK Cast and Crew Remember Heath Ledger at ShoWest Preview

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Cast and crew of the Batman Begins sequel gathered in Las Vegas Thursday for a special showing of footage of The Dark Knight. The screening was for film exhibitors attending the annual theatre-owners convention, ShoWest.

Director Christopher Nolan said he wanted to use a broader canvas for "Knight," with what he calls an "epic crime-story feel": "We've come out of the sort of gothic shadows of the first movie, that rise of crime fighting figure of Batman, we've taken it out to a wider view of Gotham, we see it at day time, we see it at night, we see Batman but we see all these other characters, we introduce a more comprehensive view of the criminal element of Gotham, how it all interrelates, we really tried to go with the epic crime story feel."

Additions to the cast include Maggie Gyllenhaal, stepping in the role of Rachel Dawes, played the last time around by Katie Holmes. Gyllenhaal said she's swapped friendly e-mails with Holmes about being part of the Batman-film legacy.

"I wrote her a little email at one point and just said isn't kind of great to be able to say you played Batman's girlfriend," Gyllenhaal noted.

Also new to the series: the late Heath Ledger, in one of his last film roles, as the Joker. Production wrapped last fall and Ledger died in January. Nolan and producer Charles Roven say all of Ledger's work was done before his passing, and no changes to the film have or will be made.

"We lost a great friend, we lost a great actor, we're not going to have him here to promote it but in terms of what our plans were for the overall campaign it's not really changing anything," Roven said.

Nolan, Roven and Bale all remembered Ledger as a hard worker, great actor and good friend.

"He was such a great creator, such a great collaborator, he was the type of actor who always brought an idea to the set, he always brought some little thing that would flesh out his character, some little piece whether it was a prop he was going to hold or a particular way of doing something that would just add something to the narrative that we had written and that I was directing, he was just a great collaborator," Nolan said of Ledger.

"Heath did a superb job, he was just committed, he fitted in so well with myself and Chris in that we all believed that we must take this seriously in order for anybody else, in order for an audience to take it seriously, Heath did that, he committed himself completely and he gave a truly defining performance," added Bale.

As for a third in Nolan's "Batman" saga? Roven said he's just trying to stay focused on the release No. 2 for now.

"This is my second film with Chris Nolan and one thing I know about him is that he's a one picture at a time guy so until this is done and out and we see how it does, I think we are just going to focus on this one."