In Staying Vertical, as in nearly all of French filmmaker Alain Guiraudie’s tonically unorthodox work, the emphasis is on the abundant possibility of pairings and practices when people get horizontal.

example, centers on a middle-aged gay man who falls in love and runs off with a sixteen-year-old girl, only to conclude with an all-male gerontophilic foursome. While the XXX action in the taut ...