La Cinquième Empreinte.

Jacques de Nisson, a rich man, has a new mistress, Lucie Cavelier. Which does not prevent him from courting Florence, the wife of his lawyer friend Forestier. One day, Jacques is found murdered and chief-inspector Candély is sent on the spot to investigate. Jean, the victim's butler, Lucie as well as Florence are suspected in turns but the real murderer is finally identified thanks to his fingerprints.