Q & A with Charlize Theron

(CBS News)

Charlize Theron's star turn in the 2003 movie "Monster" won her an Oscar. For an actress who's been dubbed one of the most beautiful women in the world, she's played some rather unglamorous characters. In fact, she wouldn't want it any other way, as she told Lee Cowan:

Even in a tank top, walking her dogs in the Hollywood Hills, Charlize Theron is radiant - disarmingly so - and so is her sense of humor.

"When people refer to you as a movie star, or a mega star, what do you think about that term?" asked Cowan.

"Well, that's how it should be!" he laughed.

You learn very quickly that, despite her A-list status, Charlize Theron is as grounded as ever.

"The greatest thing that I've learned in my journey in doing this, is that if you come with your own agenda and with your own ego and you try to kind of force something and control something, you can't make a good movie," Theron said.

It's a philosophy she carried onto the set of her new film, "Young Adult," where she teamed up with director Jason Reitman.

She plays Mavis Gary, a ghost writer of young-adult novels who returns to her small hometown to reclaim her high school flame.

The catch: He's married with kids.

"It's a woman who just never grew up," Theron said. "She just didn't. She doesn't have the tools to really cope or deal."

"It's sad," said Cowan.

"In a way, it is. But in a way, you know, it's somewhat refreshing."

And in a departure for Theron, it's also funny.

"There's definitely a moment, especially in my career, I tend to have people in tears or throwing up in bathrooms," she laughed. "So to hear them giggle was a new experience for me, yeah! I looked at my producing partner and said, 'They're laughing! They're laughing at me!'"

"Where you surprised?

"Yeah, because you never know what people are going to tap into," Theron said.

The characters audiences have "tapped into" in the past are often anything but glamorous, like her ! Oscar-no minated portrayal of miner Josey Aimes in "North Country."

"The characters that you portray so often are troubled and challenged," Cowan said.

"I'm very troubled," Theron laughed. "Lee, I'm really troubled. I am!"

"But what is it though? What is it that draws you to those kinds of characters?"

"I guess I respond to those characters because when I read them they're familiar to me," she replied. "I know them. They feel human to me. They feel real to me. They don't feel like movie people to me, you know?"

Perhaps that's why her most famous role wasn't fictional at all - portraying real-life serial killer Aileen Wuornos in "Monster."

It was a performance that earned her the Oscar for Best Actress.

But there were plenty of skeptics early on: "Financiers at the time - I will never forget it - called me at 3:00 a.m. in the morning and said, 'We just saw the first dailies and we don't understand what you're doing. Why are you not smiling? Why do you look like that?' They didn't understand why I gained weight."