Le mystérieux Monsieur Sylvain 1947

In an aero-naval base, a marine engineer who was about to deliver the name of a redoubtable spy is murdered. Shortly afterwards three different men appear on the crime scene, each of them claiming to be Monsieur Sylvain, the expected sleuth. But which of the three investigators is actually Sylvain? And what about this delightful young lady who arouses one of the police inspectors? Couldn't she be the murderous spy?

Cast:

Frank Villard
Ancelin 

Simone Renant
Françoise Dastier 

Jean Chevrier
Chantenay 

Jean Marchat
Morgat 

Marcelle Praince
The marquise 

André Bervil
The killer