Though, singer Mariah Carey played the lead role in a semi-autobiographical film 'Glitter', taking a break from pop stardom, she has acted in 'Push', grim taled new film to debut this past weekend at Sundance.

The lead role of the film that of 'Precious' Jones, an obese, overburdened 16-year-old twice impregnated by her father and beaten by her mother, is played by an unknown actress from Harlem, Gabourney Sidibe, while Carey in a supporting role plays the part of Mrs. Weiss, a welfare case worker.

Mrs. Weiss with stringy hair and no nonsense attitude, cuts an unglamourous figure as opposed to Carey's 2001 film 'Glitter', loosely based on her own rise to stardom as a singer. Panned by critics and earning only $5.3-million at global box offices, Carey starred in few movies after 'Glitter'.

Based on a novel from the New York Times Bestseller list and directed by Lee Daniels, whose production of 'Monster's Ball' won a Best Actress Oscar for Halle Berry, curiosity ran high at Sundance to see if he had been able to elicit an Oscar worthy performance from Carey, as well. The novel written by New York writer Ramona Lofton Sapphire, under the pseudonym Ramona Lofton, the controversial book published in 1996, is graphic in its description of incest. Carey says of the book: 'I was just glued to this book when I read it in, I guess '98, and it stays with you.'

So far, an early review of Push' by Daily Variety is positive, who has called the film 'courageous and uncompromising', adding 'among the many delightful surprises in the film is Mariah Carey, who is pitch-perfect as a welfare counselor and serves as this demi-tragedy's Greek chorus.'

Carey's role in 'Push' is small but pivotal, about woman who helps unravel Precious's life of monstrous home abuse and teenage motherhood. Talking to reporters Saturday, Carey described the range of emotions she had to express in her role as Mrs. Weiss in the following words: 'Mrs. Weiss is sort of the eyes of the audience, the people who don't know anybody like this in their lives. Yes it's her job ... but even someone who goes through that every day and sees these horrific things, she hears something that changes her.'

Dark though the film is, it has several comic scenes that had the audience laughing, especially the surrealistic dreams Precious creates to escape her misery. The best is the one, where she dreams that she and her mother have been transported into a Sophia Loren film on television and her mom is cursing at her in Italian.

Not the only Grammy-winning singer in the movie, Carey is joined by Rocker Lenny Kravitz, who as a nurse's aide, helps deliver Precious's second child. Witnessing history in the making, Nick Cannon's 'The Killing Room' premiered Saturday night at Sundance, a day after wife Mariah Carey's well-received drama 'Push.