(Editor’s Note: Washington Post film critic Ann Hornaday is reporting from Cannes. Check back on Style Blog from now through May 24 for updates from the film festival and follow her on Twitter @annhornaday).

It’s difficult to get veterans of the Cannes Film Festival genuinely excited about a star sighting – famous movie actors being as common as tiny yipping dogs on the city’s famed Croisette, where most of the festival takes place.

View Photo Gallery: Festival in France begins with “Moonrise Kingdom,” Sacha Baron Cohen stunt.

But it’s always special when Bill Murray shows up – probably because he says Yes so rarely to the myriad filmmakers who approach him for their movies. He was in Cannes on Wednesday for the world premiere of “Moonrise Kingdom,” a precocious coming-of-age love story that launched the festival, and that marked Murray’s sixth collaboration with Anderson. “It’s an honor to be asked back,” Murray told a packed press conference after a morning screening of the film, which received a smattering of applause when it ended, sending those aforementioned jaded critics and reporters into the Grand Palais with soothed and satisfied smiles. (“Moonrise Kingdom” opens in theaters on June 1.)

“I guess we’ve proven to each other that we’re going to work hard,” Murray continued, explaining why he and Anderson work so well together. “These are what we call ‘art films.’ I don’t know if you know what those are. They’re films where you work very, very long hours for no money. That’s all we get, is this trip to Cannes. There’s no money involved. … But fortunately, we’ve saved from other jobs we’ve worked on so we can work with Wes over and over again.”

Like Murray himself, “Moonrise Kingdom” launched Cannes on a whiff of fresh air – much like the cool, bracing breeze that is keeping the season’s often torrid heat at bay. It’s early days yet, but a sense of cautious optimism pervades the festival, which is not just about celebrating and showing film in its most pristine form (among the copious pleasures of the festival are its punctilious attention to sound and projection), but about buying and selling products we call the movies.