Mariah Carey Radically Alters Appearance for Movie

It's Mariah Carey as you've never seen her before.

The singing star, who has refused to travel without an army of beauticians and once admitted sleeping with 20 humidifiers around her bed, ditches the glamour for a movie role.

And the switch from diva to dowdy could be her best move yet, with the film, "Precious," already winning critical acclaim.

PHOTOS: Mariah Carey "before and after."

The 40-year-old sports a scruffy hairdo and unflattering blouse to play a social worker in the movie.

Set in Harlem in 1987, "Precious" tells the story of an overweight, illiterate girl who becomes pregnant with her second child at the age of 16 after she is raped by her father.

Gabourey Sidibe plays the title role after director Lee Daniels discovered her on the streets of New York.

The film - adapted from "Push: A Novel" - premiered at the Sundance Film Festival in January where it won the Audience Award and Grand Jury prize for best drama.

The film got its world premiere this weekend at the Cannes film festival, with Mariah in her more traditional blinged-out garb.

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