The Cannes Film Festival was once reserved for movie stars, but these days it’s another date on the roving international party circuit as apt to draw Rihanna as Steven Spielberg.

While Spielberg is heading the jury (with Ang Lee, who stole the Oscar from him, as well as Nicole Kidman), pop diva Rihanna will be at the festival, we hear, for de Grisogono’s annual party with Heidi Klum, Paris Hilton and Irina Shayk.

Before Cannes can even kick off Wednesday with “The Great Gatsby,” Eva Longoria arrives in Paris for the Global Gift Gala at the Four Seasons tomorrow to honor David Beckham.

Hot Cannes parties are expected to include Calvin Klein and IFP’s Women in Film bash for guests Kidman, Rooney Mara, Carey Mulligan and Naomie Harris and IWC Schaffhausen’s filmmaker dinner at the Hôtel du Cap with Robert De Niro, Tobey Maguire, Cate Blanchett, Naomi Watts, Kevin Spacey, Ewan MacGregor and Bradley Cooper. Others making the scene include Marion Cottillard, Jeremy Renner, Orlando Bloom, Robert Redford, Jane Fonda and Tilda Swinton.

Designers descending on Cannes include Giorgio Armani, who’ll launch a new store, and Elie Saab, who’s opening a showroom at the Martinez Hotel. Model Natalia Vodianova will co-host a charity bash called The Beach Ball.

Of course AmfAR still throws the mother of all Cannes bashes, with expected guests Janet Jackson, Duran Duran and Elton John, and where Shirley Bassey will play. Nikki Beach is back with three Cannes pop-ups, including one at the coveted Carlton Beach and another at the JW Marriott rooftop. The intriguing-sounding Hollywood Boudoir Villa is a gifting suite and spa.

Oh, right, there are films, too. Besides new movies from Steven Soderbergh, the Coen Brothers and Sofia Coppola, there’s a touch of classic Hollywood: Jessica Chastain is hosting a 50th-anniversary screening of “Cleopatra,” Bernardo Bertolucci is showing a 3-D version of “The Last Emperor” and Kim Novak will be a guest for a restored version of Alfred Hitchcock’s “Vertigo.”