[1] Policarpo De 'Tappetti is a modest ministerial employee of Umbertine Rome: he is precise and diligent, but his excesses of zeal attract him the antipathy of Cavalier Cesare Pancarano di Rondò, his severe office manager, as well as aristocratic aristocrat convinced that he is related to the reigning Savoy dynasty, which is why he spends good money on complex genealogical research in order to ascertain its veracity.

The respective families of the two meet by chance while walking on the Pincio, and the son of Pancarano di Rondò, Gerolamo, falls in love with Celeste, the young and pretty daughter of Polycarp; in front of her insistent court that Gegè of her, a fatuous and superficial character of her, the girl appears rather perplexed, but she agrees to become engaged to him at the insistence of her parents, who foresee for her a brilliant wedding.

So to distract Gegè from the idea of marrying Celeste , the knight approaches Edelweiss, a subretta of café-chantant with whom the young man had previously been in love, and convinces her to be seen in a bathing suit on the beach of Ostia, where Gegé plans to go with his girlfriend.

In the meantime Celeste falls in love with Mario Marchetti, a serious and honest young mechanic who teaches her to type, wanting the girl to find a job as a typist.

Immediately afterwards, moreover, the scholars who on his behalf were looking for genealogical documents certifying his alleged blue blood inform him that an ancestor of his was called Biancamano not because he was related to the reigning Savoy dynasty, but because of his profession as a painter.