Gabourey Sidibe isn't ashamed to say she was wrong. It's a mistake she will carry to ruby red carpets from now until Oscar night and beyond.

"I was a smart girl but now I have a different knowledge of life and what life can be," the 26-year-old star of "Precious" said during the Toronto International Film Festival.

"I didn't think I had any business going to the audition, I didn't think I could get an acting job with one audition. I wasn't an acting student, I never wanted to act. The biggest thing I learned is that I was wrong about what I thought I could do. I thought I'd be a receptionist my whole life."

She was a psychology student and a receptionist in early September 2007 but after a world-changing Monday, Tuesday and Wednesday, she became the lead of the movie based on the novel "Push" by Sapphire.

When Sidibe met the media, in hotel room interviews and on a football-field version of a dais with such luminaries as Oprah Winfrey, Tyler Perry and Mariah Carey, she sounded and looked little like Claireece "Precious" Jones.

Her natural speaking voice is higher and brighter, and her posture that of a confident New Yorker, not a defeated, abused and twice-pregnant teen.

"I left it at 'Cut,' " she says of Precious' deep voice. "I'm not a trained actress, I don't know any better than to stop being the character when the director says cut." Besides, "It's insane to take that home."

Still, her instant vocal adjustment would always catch the cast and crew by surprise. They also were caught unawares during a revelatory scene with Sidibe, Mo'Nique as her mother and Carey as a social worker.

"That scene was certainly one of the harder scenes of the film, just because it was the answer in a lot of ways. Maybe it wasn't the greatest answer but it was an answer to why Precious' life was the way it was. ...

"While we were filming it, we were crying. None of us was supposed to be crying but it was just so deep and so raw that we couldn't help it. Cameramen were crying."

Mo'Nique and Sidibe are trapped in some of the most toxic, hateful mother-daughter scenes ever filmed but that didn't spill over once the cameras shut down.

"We would hug each other," she said. The volatile, violent relationship between Precious and her mother, Mary, made Sidibe and Mo'Nique love each other more, the young actress said.

As a student of psychology, both informally and formally at New York's Mercy College, Sidibe had read a lot of books on child victims of pedophilia and incest.

"I wasn't just concentrating on that like a weirdo, but certainly I've read a lot and even after getting the role, I continued to read and I kind of know the psychology behind someone who's been abused and they kind of run into themselves."

They attempt to hide within themselves and that's how she played Claireece. "She assumes she's the ugliest person in the room," and she mumbles and is almost like a hermit. "She doesn't want to be seen; she doesn't want you to notice her."

In real life, Sidibe is one of six children of Alice Tan Ridley, an R&B/Gospel singer. She's upbeat and relaxed, whether facing a throng of reporters and photographers who direct many of their questions to Winfrey or in a hotel room with her shoes kicked off, her hair pulled back and nibbling on a late breakfast.

She emerged from a field of 500 hopefuls and recently was honored for her acting at the 13th annual Hollywood Awards, part of the Hollywood Film Festival. In Toronto, director Lee Daniels said that just as Precious changes, so did Sidibe.

"She changed from the beginning of the film to the end of the end. I can't take credit for it. Her spirit changes. I watched her change from this receptionist to someone who has so much self-pride."

It was Henry Ovalles, assistant director of Lehman Stages at New York's Lehman College, who suggested she audition.

"They were looking for a certain type of girl, and there weren't a lot of girls who fit that mold and so he called me. Even though, at that point, I hadn't been on stage at all for three years. Maybe four, even."

He told her on a Friday but she was pretty sure she would skip it, having just returned to her studies in September 2007. Her mother suggested she revisit the book but come Monday, the college student still wasn't sure if she would show.

"Somehow it was either go uptown to the audition or downtown to school. I ended up at the uptown side of the street, so I went to the audition and it worked out pretty well."

The pair handling the casting gave her about 90 seconds worth of dialogue to recite and then double-checked her e-mail and phone number and assured her they were impressed.

Really? "Oh, believe us, we've been here all day. Really good," they told her.

She left for work and within an hour was invited for a callback. The next day, she was handed two scenes. "When I finished, nobody said anything. Complete silence for like a good 10 to 20 seconds. ... Just staring at me like I'm in limbo."

Then, casting director Billy Hopkins screamed, "Get her a script right now!" and told Sidibe she would meet Daniels. She left and, within 30 minutes, got a call about that appointment for the next day.

"I go into Mr. Daniels' office and we sit and talk about nothing in particular for a very long time -- like 45 minutes to an hour. Meanwhile, I'm itching, cause I'm ready to audition again," and she's thinking if he would quit talking, she could audition and get out of there.

After some more conversation about college (he had dropped out, she would have to take a hiatus), he said, "I want you to be in my film." To which she said, "Shut up," and then, "As what?"

Sidibe recalls, "Even though I had only auditioned for one role, I thought that maybe somehow he meant you can be dishwasher No. 3 in this one scene. He said, 'I want you to be Precious,' and I started crying."

And now she and her co-stars are the ones moving audiences to tears, too.

Post-Gazette movie editor Barbara Vancheri can be reached at bvancheri@post-gazette.com or 412-263-1632.

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