Paris Belongs to Us
Paris nous appartient (original)
Starring Betty Schneider, Giani Esposito, Françoise Prévost, Daniel Crohem, François Maistre, Jean-Luc Godard, Jean-Claude Brialy, Jean-Marie Robain, Claude Chabrol, Jacques Demy
It's a mystery and drama movie, and has a rating of 6.8 out of 10 from Imdb which is usually fine for this kind of movie.
Watch it here
Not found streaming from Austria.