The singer plays a social worker in Precious, a tough drama about an illiterate New York teenager pregnant with her father’s baby.
The film is in the festival’s Un Certain Regard competition, which aims to recognise unusual and original films.
Carey joined her co-stars, who include musician Lenny Kravitz, on the red carpet at the Palais des Festivals. Meanwhile, in the main competition, Bright Star, which tells the story of the poet John Keats’ love for his teenage neighbour, drew a similarly glamorous audience for its official screening. Among those who attended the star-studded event were Desperate Housewives’ Eva Longoria Parker and the silver screen’s queen of chic, Juliette Binoche
The poet is played by Ben Whishaw, who won plaudits — and a Royal Television Society award — for his part in TV drama Criminal Justice, while Abbie Cornish plays his love Fanny Brawne.
Whishaw said he “fell in love” with the poet John Keats while playing him in the film.
“I didn’t really know very much about him at all and I think I had a prejudice about romantic poets generally,” the actor said. “But I’ve grown to love the luxury of his writing, the sensuality of it.
“When you investigate a person that deeply you fall in love with them a bit — learning about his life, reading his letters, talking about the love affair,” Whishaw added.
Director Jane Campion, who won the Palme dOr in 1993 for The Piano, said her 13-year-old daughter Alice had given her some of the inspiration to create the character of Fanny.
Campion — the only woman ever to win the Palme — said returning to Cannes for the 62nd festival was a very emotional experience.
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