Setting aside sequels and superhero movies for a moment, many eyes in the moviemaking world are transfixed right now on writer/director Oliver Stone and his latest project, "World Trade Center," Hollywood's fullest exploration yet of 9/11. And according to the cast, there's a feeling of being a part of history that sets this project apart from anything else they've ever worked on.

"We shot for six weeks in New York," Brad William Henke ("North Country") recently remembered. "Just talking to people when they hear that you're shooting this film, it's such a responsibility. 'Oh you're making a film about 9/11. What is it? I'll tell you what I was doing that day.' "

"It was such an intense, unbelievable experience," Maggie Gyllenhaal echoed, softening her voice. "He's pushed me more than any other director ever has. It's hard stuff. It all takes place in the day, and reliving that day is ..."

Trailing off, the 25-year-old actress stared down as if she could once again see Stone's meticulously detailed Ground Zero set, where she was surrounded by co-stars Nicolas Cage, Maria Bello and Michael Pena as well as real-life survivors serving as advisers.

"The character I play, I met him," said Henke, cast as a loved one waiting helplessly for word on those trapped in the collapsed towers. "He told me how he felt, what happened, how I should feel. It's a big responsibility."

"I'm the wife of someone who's trapped, and I'm pregnant in the movie," Gyllenhaal said of the emotionally charged process of meeting her real-life alter ego, the wife of Pena's Officer William Jimeno. "I met her a lot of times. I'm not really playing Alison, but I am on another level. She's got such a huge heart. I mean, that's such a clichéd thing to say, but I feel her heart. I feel her heart, and I feel that it's still kinda broken about what happened to her husband."

According to Henke, such interaction is invaluable as the actors try to capture a level of emotion most people can only imagine. "It is additional insight that really helps you," Henke said of his somber friendship. "He said, 'I was the guy who had it together all day. I was trying to be strong for everyone. I was worried how I was to support two families if someone died.' That kind of stuff. Then he said when his situation ended up OK, he just lost it. That, for me, was very helpful."

Both actors admit that fostering such connections to a subject matter that touched everyone so personally can be a drain. "I have really high hopes for that movie," Gyllenhaal sighed. "It's very hard. ... It's been overwhelming and a lot of work."

Echoing the recent comments of co-star Jay Hernandez (see "Jay Hernandez Pulls Back Curtain On Oliver Stone's 9/11 Movie"), Gyllenhaal and Henke praised the dedication of Cage and the other actors, but he insisted that Stone's obsession with getting the tone right has trumped them all. "It's just been a great experience working with Oliver Stone," Henke marveled. "I can't describe what a great director he is. He creates the tension on the set for you, but he's also so helpful and nurturing when he directs you."

"A lot of Oliver's movies are like operas," Gyllenhaal added, insisting that "Center" will aim to echo the power of his best historical dramas. "They're painting a really emotional, really committed portrait of a time. ... That's what he pushes you to — a really committed, honest opera."

The film could conceivably be ready for a late summer/ early fall release, perhaps around the same time as the fifth anniversary of the events it depicts. Gyllenhaal and Henke think such a release would be appropriate, since Stone is aiming to construct a history lesson that will commemorate the disaster for years to come.

"When we were rehearsing, someone was asking, 'Hey, can I change this line or can I do this?' and he thought about it for a second and said, 'No, because if someone watches this film in 20 years, if they weren't born until 20 years from now, they might not know that [expression],' " Henke said, grinning admiringly. "I thought to myself, 'This man's thinking about making a film, and he's thinking about someone who's born 20 years from now watching it, and he wants them to be informed about really what it was all about.' And that really put it in perspective."

"[He's making] a memorial service, honoring what happened," Gyllenhaal said. "That is how it feels. ... It's all these feelings — it's numbness, it's anger, it's fear, it's pain, it's so many things. And you go through it, as Oliver demands that I do."

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