In the "Red Cat" Kaschemme, the unemployed actor André is considered to be a gang boss who, with his charm, meets the interest of Gloria, the daughter of the US jewel dealer Jefferson, who is said to have just acquired the famous "Halifax" brilliant. For him, the crook Pitou is interested, who tries to flatter himself with the Jeffersons. When Pitou Gloria sees with the supposed gang boss André, he believes that this too could be after the "Halifax" and wants to put him on the spot.