In the early 1950s, the popular radio show "La Kermesse aux Étoiles", hosted by the famous Jean Nohain, mixing lottery games and performances of various artists, will be disrupted by the adventures of a man and his fiancée seeking to recover a dangerous bottle of perfume (explosive) which was unfortunately mixed with the prizes to be won ...
A journalist who deals with the column "courier du cœur" has the absurd idea of launching an investigation into the death of a pianist whom he claims to have been murdered. To dazzle his wife, a reporter for the newspaper, he disguises the facts in such a way that the police suspect him, then declare him guilty. It takes a number of adventures to get him out of this mess and get him back into his section.
For the past few weeks, revolt has been brewing in the Kingdom of Naples. The handsome Castelli is at the head of the conspiracy that wants to put an end to the reign of King Murat. To carry out his plan, he decides to infiltrate the court in order to become an intimate of the king. But his ploy works too well: he manages to enter the court thanks to his talents as a singer and very quickly seduces Queen Geneviève. But this imprudence costs him a lot. He is soon arrested by the king's men and immediately condemned to death.
On his way to Paris, Casanova keeps on collecting female conquests, does not shy away from duels and gets into many a colorful adventure. Once in the capital, the fearless knight saves the honor of a great lady, conquers the niece of his implacable enemy but courts disaster for love of Coraline, a faithless opera dancer.