Mariah Carey And Gabourey Sidibe Became 'Besties' On 'Precious' Set

'Mariah and I would sit and talk about fashion and perfume and jewelry,' actress says of her co-star.

There's no other way to put it: [movie id="415966"]"Precious"[/movie] is brutal, an urban horror story overwhelming in its exploration of familial abuse, rape, teenage pregnancy and the hopelessness that pervades one broken family's life. A thoroughly un-diva-like [artist id="976"]Mariah Carey[/artist] appears as a social worker and Mo'Nique has virtually locked down an Oscar nod for her turn as a sadistic mother, but at the center of it all is the 16-year-old title character played by newcomer Gabourey Sidibe.

She's an untrained actress, contended daily with material that is beyond difficult, and yet on set had the time of her life. "We would do really, really intense scenes where I'd be crying or saying, 'My dad raped me,' and then when the director would say, 'Cut,' I'd be giggling," Sidibe, a New York native in her 20s, told MTV News. "I don't have any formal training how to be an actress. I don't know any better than to stop being the character once the scene is over."

The crew didn't quite know how to react to her light-switch-like transformation and, even now, after "Precious" won both the Grand Jury Award and the Special Jury Prize at Sundance, the people she meets tend to confuse Sidibe with her character.

"They'll start to talk to me in a more careful tone or be really wary of me," she explained. "They'll want to coddle me or they see me in the street and they'll want to hug me and rub my back and tell me everything will be OK. But it's cool, I like hugging."

As the actress said, she's got a "big personality," and she bonded with her big-name co-stars on set. "Mariah and I would sit and talk about fashion and perfume and jewelry," she said. "It was like sitting in junior high and talking to your bestie. She hated her wardrobe! We all hated our wardrobe!"

She hasn't yet met Oprah Winfrey, who has championed the film since Sundance, but has a strategy in place for when she does. "I have plans to imprint myself in her life," she laughed. "She's about to be my fairy godmother. She has no idea!"

Sidibe has a lot of love to give and her co-stars loved her right back. "Everyone fell in love with her on set," said Paula Patton, who plays a teacher at a special-education school Precious begins attending and who begins to pull the teenager out of her despondent state. "She's the best. She's a ray of sunshine. She put on this amazing performance, but she's just a bubbly girl who loves to dance. She has the gift."

The film comes out on November 6. Until then, Sidibe is back to her normal life, working at the Fresh Air Fund and commuting daily to an office. She still finds it hard to imagine that she's actually the star of a motion picture, one based on a book she read years ago and immediately loved.

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"I fantasized about playing Precious, but didn't take it seriously at all," she said. "But then when we were filming, I was a creepy fangirl. If we were going to do something that was different, I would stand up on my soapbox and be like, 'No!' "

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