Marion Cotillard, Matthias Schonhaerts, Rust & Bone
Marion Cotillard is the odds-on Best Actress favorite at the Cannes Film Festival 2012 for her performance as an invalid in Jacques Audiard's De rouille et d'os / Rust & Bone. Cotillard has already won a Best Actress Academy Award, a British Academy Award, and two Césars, but she has never won a Cannes Award in the Official Competition. Barring an upset, this will be her year. [See also Cannes Best Actor Prediction.]
Now, who could be the "upsets"? Well, there are a number of possibilities (and of course, ties aren't infrequent at Cannes).
Veterans Isabelle Huppert and Emmanuelle Riva, the two female stars in Michael Haneke's acclaimed Amour / Love, could share the Best Actress Award -- as was the case with the nearly all-female Volver cast in 2006. Or perhaps Huppert and Riva might share a "Best Ensemble" Award with fellow Amour player Jean-Louis Trintignant. That has (sort of) happened in the past: Sidney Lumet's Long Day's Journey into Night, which back in 1962 earned top awards for Katharine Hepburn, Jason Robards, Ralph Richardson, and Dean Stockwell.
Though despised by just about everyone, Ulrich Seidl's Paradies: Liebe / Paradise: Love may earn Margarethe Tiesel the Best Actress trophy. Tiesel's performance did get good reviews despite her character's shortcomings, and the actress also earned quite a bit of praise for her "courage" in the sex & nudity department.
Nicole Kidman in another controversial and much-disliked movie, Lee Daniels' The Paperboy. But as a sexpot -- or rather, sexboilingkettle -- who gives Zac Efron a golden shower, Kidman does have a chance, especially when her The Paperboy character is seen next to her journalist Martha Gellhorn in Philip Kaufman's Hemingway & Gellhorn, which was also screened at Cannes (though not in competition).
Isabelle Huppert again in Hong Sang-soo's In Another Country, in which she plays three different roles. Now, since Huppert has already won two Best Actress Awards at Cannes, that makes her a somewhat less likely contender this year. Another possible handicap: to put it mildly, In Another Country wasn't exactly a critical favorite.
Cristina Flutur, as a woman still in love with her former companion, a (now) Orthodox Christian nun (Cosmina Stratan), in Cristian Mungiu's Beyond the Hills. Icing on the cake: Flutur's character is possibly either mad or possessed by the devil.
Kristen Stewart as the free-spirited Marylou in Walter Salles' On the Road. Considering that Stewart's role seems to be subordinate to those of Garrett Hedlund and Sam Riley, her chances of a Best Actress win are somewhat diminished. But then again, Stewart and Hedlund received most of the praise bestowed on Salles' film adaptation of Jack Kerouac's novel. Also, a relatively small role in Denys Arcand's The Barbarian Invasions didn't prevent Marie-Josée Croze from taking home the Best Actress Award nine years ago.
Marion Cotillard, Matthias Schonhaerts / Rust & Bone picture: Cannes Film Festival.