When the swindler La Spada and his accomplice José come out of jail in Madrid, they decide to pull a really great swindle: nothing less than to discover and sell a third picture of the famous Goya's Maya. They engage the renowed Scorcelletti who can imitate any picture and who lives in Rome. Afterwards, with the help of the beautiful Eva, they convince the celebrated art critic Francisco Montiel of the existance of a third Maya and let him find the picture. When the swindlers are on the point of selling the faked maya to an American millionaire, Scorcelli comes back from Rome to sell one of his six other maya pictures.
Duclos's son, a worldly gangster, is compromised in a case of which he is innocent. The proof of this innocence is in the hands of a "competitor", the Marquis de Chemantel de Beauvoiron, a misguided aristocrat. He asked for $ 10 million to cede the document. Duclos will then imagine Chemantel contracting $ 10 million in life insurance for his son. As he discovered in Rome a tramp, a look-alike of the marquis, he will bring this man to Paris and arrange for him to die accidentally.