'American Hustle' Stars Christian Bale, Amy Adams on Getting Into Character (Video)

Writer-director David O. Russell also talks to THR about how much of his film based on the real-life Abscam scandal is fictional.

Much has been made of how American Hustle writer-director David O. Russell embellished and extrapolated upon facts from the real-life Abscam scandal that serves as the basis for his movie. There's even a title card at the beginning of the film that reads, "Some of this actually happened."

Talking to The Hollywood Reporter in New York last weekend, Russell revealed how he modified Eric Warren Singer's script to create more of a character-driven narrative.

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"The original script … laid out the characters and what they could be, and some of the logistics of what was more procedural," Russell explains. "As a filmmaker, and what I think I can contribute, is more about the character, more about the heart and soul of the people. It's about how they're loving and how they're living and how they're grappling with reinventing themselves. That's what I wanted to focus on."

With respect to how much of what's in the movie "actually happened," Russell says, "they each are based on people that looked or behaved in some ways like they look and behave. And they're all in a predicament that feels a lot like the predicament that they're in."

Star Amy Adams also admits that "a lot of it is very fictionalized and David O. Russell-ized."

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But Adams' onscreen paramour, Christian Bale, really committed to portraying the real-life inspiration for his character, Irving Rosenfeld, by gaining weight, particularly around his midsection, and even shaving his head to help construct Irving's elaborate comb-over -- something that Russell seemed a bit hesitant about.

"I would see David every month or something as he was writing this, and he noticed, he was like, 'Whoa, what's going on? You're putting on a lot of weight,'" Bale explains. "And I'm like, 'I'm doing it.' I said, 'I can't picture Irv as anything but this rotund ball of energy with his shades and his comb-over, so I want to be shaving my head and having a comb-over and all of that.' "

Bale notes that Russell ultimately came around to his transformative character choices, including what Bale points out is an ironically unconvincing hairstyle.

"One thing that I found to be a really nice insight into this guy is the fact that he's such a consummate con man, but he does this comb-over that cons nobody, you know, about him having a full head of hair. I just love that contradiction," he says.

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Adams, meanwhile, said she had a natural tendency to commit to perfecting her character's fake British accent, but working with Russell and his fast-paced process helped her create one that was more noticeably artificial.

"I tend to be a perfectionist, and working with David actually made it easier that it's fake because he's in the moment and thinking and creating this pace on set that really, you can't overthink things," Adams explains. "Once I let go of the accent being perfect, I think it helped inform the character as well, and it opened up these opportunities."

American Hustle opens in New York and L.A. on Dec. 13 and expands to theaters nationwide on Dec. 20. The film was nominated for seven Golden Globes and two SAG Awards earlier this week.

Watch THR's interview with the cast and director above.