How does one prepare to play a horrendously cruel, masterfully manipulative teenage girl?

Just think back a few years, says Evan Rachel Wood (search), star of the dark high-school satire "Pretty Persuasion." (search)

At first glimpse, her eloquent, poised Kimberly Joyce is the picture of politeness as she shows a new student around their WASPy institution.

But when the racial epithets and sordid sexual comments start flying out of her mouth, you quickly realize she's a wolf in prep-school clothing -- a girl who could effortlessly out-snark any "Heather" or "Mean Girl."

In an elaborate revenge plot, Kimberly enlists two friends to join her in accusing an innocent teacher (Ron Livingston (search)) of sexually molesting them. While the scandal blows up into a nationally televised trial, she amuses herself by using everyone around her.

"It's like the world is an orchestra and I'm the conductor," her character says blithely.

17-year-old Wood says she didn't have to look too hard to find her inspiration.

"I got home-schooled after one year of junior high, but unfortunately I couldn't escape the whole high-school experience," she says. "In acting class, I still had to deal with those girls who stab you in the back with smiles on their faces.

"I would come home crying all the time."

But she's not crying anymore. With a slew of young-actor awards for her role in 2003's gritty "Thirteen," she's becoming one of Hollywood's hottest up-and-comers.

The battle scars, however, are still fresh. Wood betrays only a hint of glee when she describes a recent encounter involving the girl she based her "Pretty Persuasion" performance on.

"Someone told me, 'So-and-so says you guys are, like, best friends!'" Wood says indignantly.

"I was like, 'Oh really? Is that what she's saying now? Let me clear this up: She was a b-tch and she made my life hell. Spread it around.' "

To hear the sweet Wood sound off this way is startling -- but it affords a tiny glimpse of her ability to play Kimberly.

The film's director, Marcos Siega (search), says Wood is wise beyond her years. "She's a freak of nature!" he says. "She's extraordinary. I'm doing a movie about 40-year-old men, and I think she could play a 40-year-old man."

But Wood won't let the praise go to her head -- because she knows what can happen.

"I've seen some pretty cool people get corrupted by celebrity. Really sweet, shy people suddenly feeling like they're too good for you," she says. "It's just stupid. It's not the most important thing. You just have to be aware that this could all be gone tomorrow -- and know who your real friends are."

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