CANNES, France -- “Triangle of Sadness” is a comedy about fashion, trends, social media influencers, how to set yourself apart but not too much, the enduring power of social hierarchies, the #metoo and virtue-signaling maelstroms.

The pitch for “Triangle of Sadness” goes like this: the film starts in the fashion world, then the action moves to a cruise ship to finally end on a deserted island, with a male and