In Paris, a young girl is found dead in a Parisian square, wearing an evening dress. Commissioner Maigret will try to identify her and then understand what happened to the victim.
The Bouvier-Sauvages, a large aristocratic family, meet the much more modest Martin family when their children's wedding is announced. For the occasion, the future bride and groom offer their parents DNA tests, which will reveal their true origins. The results are totally unexpected and will make the effect of a bomb.
