A young reporter solves a mystery crime. The fictional reporter is Joseph Rouletabille. He works on a complex, and seemingly impossible, crime in which the criminal appears to disappear from a locked room.
Serge Reggiani
as Joseph Rouletabille
Pierre Renoir
as Professeur Stangerson
Janine Darcey
as Sylvie
Arthur Devère
as Father Jacques
Marcel Herrand
as Larsan / Ballmeyer
Gaston Modot
as Arthur
Lucien Nat
as Robert Darzac
Hélène Perdrière
as Mathilde Stangerson
Fabien Loris
as Julien
Robert Le Fort
as Secretary