READ MORE: The Complete Cannes 2015 Guide On Thursday night in France, three days before Jacques Audiard's stirring social-realist drama-turned-action-thriller "Dheepan" won the Palme d'Or at the Cannes Film Festival, the Lumiere Theater shook with applause and an extended standing ovation following the movie's premiere. A very different response greeted the announcement of the prize on Sunday, next door at the Debussy theater, where throngs of international press watched a live stream of the ceremony: "Light boos, some applause, clear disappointment," reported one person in the room. So it goes at Cannes, a festival that thrives on ambiguous perceptions of quality, in which critical reactions, the arbitrary decisions of a small jury, and the whims of the industry are constantly at odds.