"There was a 10 minute break while I cried. I had to go hide behind a building. I just lost it and started crying," she says. "I know I'm playing this woman who's supposed to be — it's her job — to be unemotional, but I still feel things. And I wasn't going to be able to do the scene again without letting out, without having a good cry."
Because of her busy schedule, Chastain nearly didn't do "Zero Dark Thirty"; she was slated to be filming something else at the time. Producer Megan Ellison, whose Annapurna Pictures financed the film and who knew Chastain from producing "Lawless," played the go-between.
"I got a text from her that said: 'If I ever ask you for anything in my life, it's to call me right now for five minutes,'" recalls Chastain.
Bigelow, the Oscar-winning director of "The Hurt Locker," was set on casting Chastain.
"We moved heaven and earth for this woman," says Bigelow. "This is a fairly complex piece and required somebody with great verbal agility. But as importantly, the precision of her carefully calibrated and nuanced performance, I've seen in her other work but never to the extent I've seen in this."
It's a kind of magic act that Chastain does that can even surprise her directors. Jeff Nichols, who directed her in "Take Shelter," had heard good things about her and found her charming, but because it was before most of her films saw the light of day, her talent was evident only once work started.
"I hadn't seen anything of hers that was this lightning rod thing," said Nichols. "I just cast her. I didn't really know what I had until I got there."
The daughter of a firefighter and vegan chef, Chastain grew up in Northern California knowing from an early age she wanted to be an actor. She trained at Juilliard School of Drama but didn't catch a real break until Al Pacino cast her in a Los Angeles theater production of "Salome."
"I've been fighting so long," says the 35-year-old Chastain. "I'm not 17 years old. I trained in this. I did a lot of theater. I was playing dead bodies on TV shows. This is the first time I'm getting offered really incredible roles."
Now, her only problem is saying no. With just a few hours to go until she's due on stage, Chastain shrugs at over-committing herself:
"A year and a half ago, I didn't know my life was going to be like this."
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