The film world's grandest red carpet will be crowded with celebrities as usual for the Cannes Film Festival, though plenty of weighty issues and ideas will mix with the glitz. With Tom Hanks comes religious debate as "The Da Vinci Code" opens Cannes on Wednesday. With Oliver Stone comes a glimpse of his upcoming Sept. 11 drama "World Trade Center." With Sarah Michelle Gellar and Dwayne "The Rock" Johnson comes a look at Los Angeles of the near future on the cusp of social and environmental chaos in "Southland Tales," an offbeat combination of musical comedy and sci-fi thriller. With former US Vice President Al Gore comes a dire message in the documentary "An Inconvenient Truth" that the dangers of global warming are real, imminent and potentially catastrophic. Even the comic-book world's favorite mutants are turning somber with a dark, apocalyptic battle in "X-Men: The Last Stand." Thank goodness talking animals will be on hand to lighten things up, with Bruce Willis as mouthpiece for a rascally raccoon and Garry Shandling providing the voice of a cautious turtle in the animated comedy "Over the Hedge." One and all will be marching the red carpet that swoops up an imposing staircase to the festival's main theater, running a gauntlet of tuxedo-clad photographers on each side who try to out-shout one another to catch the stars' attention. "It is the red carpet of all red carpets," said Willis, previously at Cannes with "Pulp Fiction." "That was just completely overwhelming," Natalie Portman said of her first experience on the Cannes red carpet at last year's festival for "Star Wars: Episode III - Revenge of the Sith." "I've never seen so many photographers and fans. I've never seen anything like that before," said Portman, who co-stars in this year's Cannes entry "Paris, I Love You," a collection of 20 short films set in the French capital from such directors as Gus Van Sant, Alexander Payne, Alfonso Cuaron, Wes Craven and Joel and Ethan Coen. "Da Vinci Code" director Ron Howard is an old hand at Cannes with such films as "Willow" and "Far and Away." Playing opening night at the 59th Cannes festival caps a huge marketing blitz for the adaptation of Dan Brown's best seller, which debuts in theaters worldwide Wednesday, Thursday and Friday. "I think it's going to be kind of nice to go and get it out of the way," Howard said. "It's an honor to be selected. This is a huge international film festival, and this is a very international kind of movie." Always representative of world cinema, the Cannes lineup includes Pedro Almodovar's fanciful "Volver," reuniting him with Penelope Cruz; Alejandro Gonzalez Inarritu's drama "Babel," with Brad Pitt, Cate Blanchett and Gael Garcia Bernal; Ken Loach's "The Wind that Shakes the Barley," an Irish historical saga featuring Cillian Murphy; and "The Caiman," a satiric assault on Italian Prime Minister Silvio Berlusconi, directed by Nanni Moretti, whose film "The Son's Room" won the top prize at Cannes in 2001. Director Oliver Stone comes to Cannes for a 20th anniversary presentation of his Vietnam masterpiece "Platoon," which will be preceded by preview footage from "World Trade Center," with Nicolas Cage in the story of two policemen trapped in the rubble of the twin towers.