She has been a serial killer, a crusading miner and a harried police detective. But a cinematic shrinking violet? Not so much.

So you might wonder how Oscar winner Charlize Theron wound up as glorified eye candy in Will Smith's Hancock.

REVIEW: Muddled 'Hancock' can't quite save the day

But bear with her — and her character, Mary — and all will be illuminated.

"I think it's really nice when you're playing the female role in this kind of movie and people can't predict what she's going to be," Theron says. "People think of me as very serious, and there's an aspect of Mary that was that, but it was nice for (Smith) to trust me with the material."
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Hancock, which opened Wednesday, stars Smith as the foul-mouthed superhero, Jason Bateman as his accidental publicist, and Theron as Bateman's wary wife. It's her first big-money, bangs-and-whistles action film since she won an Oscar for playing a murderous prostitute in 2003's Monster. She then delivered gritty turns in North Country and In the Valley of Elah. Yet casting her in Hancock was a no-brainer for director Peter Berg.

"She felt like one of the actresses who could hold her own with Will. She has that physical thing cooking, the charisma thing, the twinkle in her eye, the killer smile, just like Will does," Berg says. "She brings this incredible visual energy coupled with this alive, charismatic, devil-may-care acting style."

Theron, 32, sees little of herself in Mary, a perfectly coiffed California Stepford spouse.

"I feel like, in the beginning of the movie, she's hiding so much of who she is, and she's living such an organized life, where everything is run on a schedule. She's controlling the situation of what their home life is. I'm definitely not that."

Theron is a perfectionist in other ways, however, which gets under her actor/director boyfriend Stuart Townsend's skin.

"I don't like things lying around in the house that are not being used. I don't like waste. So I drive Stuart somewhat insane," she says. "I'm going through the house going, 'When was the last time you used this? You haven't used this? It's going somewhere where it will be used.' A year later, he's like, 'Where did you put that thing?' I don't know. He's like, 'Babe, you're killing me.' "

For someone who seems to specialize in playing intense, often humorless women and who exudes a cool perfection on red carpets, Theron displays a loose, incisive wit. After fielding a question about how gender-neutral her recent roles in North Country and Elah seemed to be, Theron makes a confession. "Basically you're saying I'm a man," she says. "I am a man. It's totally fine. We can tell the world."

And what about her recent spate of hunky co-stars, including Martin Henderson in September's Battle in Seattle and Viggo Mortensen in November's The Road? "That's why I wanted to talk to you, so I could really let people know how hard my life is. I need them to understand how difficult it is," she deadpans.

Berg calls her "a scrappy, fun girl. She became the kid sister I always wanted — fun and real and willing to get her hands filthy, not just dirty."

He even has a nickname for Theron. "She's Chuck. She's just one of the guys."

Bateman, Theron's Hancock hubby and former Arrested Development co-star, agrees.

"There's nothing dainty about her," he says. "She can tell a joke, she can hear a joke. She's got a great laugh."

And a killer wardrobe. Theron, the face of Christian Dior's J'Adore fragrance, has piles of designer frocks.

"I make a point to try and keep my closet to a place where it's like, I'm one person," she says. "What can I really, really use? I'm always thinking about that."

So it's good to be Theron's friend when she's downsizing?

"If you have my shoe size, which very few of my friends do!" she retorts. "I'm a 9 or a 10. My mom is always like, 'Ugh, you're killing me. You're my daughter and you're supposed to have my shoe size.' "