Passage secret (1985)

August in Paris means everyone is on vacation, and that's when the burglars decide to strike in Passage secret (1985). A group of ambitious thieves hatch a plan to make half of Paris part with its worldly possessions--until an architect catches them red handed! This guy isn't a saint himself, though, and instead of turning them in he gets involved in the game. It doesn't help that he has his eye on the eye-pleasing Dominque Laffin, an unlucky lady the thieves have been helping out.