It takes all of two minutes for Bruno Dumont’s latest film, “Slack Bay,” to poke fun at his bourgeois protagonists. A car emerges and with it is a woman who stands up, excited. “Ooo! Mussel-gatherers, ...

André Van Peteghem, the bird-brained head of a haute bourgeois family so inbred that most of its members can’t sit down in a chair on the first try, bumbles around his villa-slash-Egyptian-mausoleum ...