In the prologue, Sacha Guitry says: «The sound cabin enters the stage. Already, the helmeted operator is listening.» The camera shows a closed, dark Citroen van coming from the street. It features the RCA logo on the right-side door, and on the van's body, the Pathé-Cinéma logo and the words «Pathé-Cinéma Enregistrement Sonore». On the front of the van's body, «Paris Seine».