Count Borraccilo lives in luxury but does not pay taxes and for this he is targeted by the tax agent Gaetano Pellecchia, who asks his friend Mario for help.
Roberto Maldi, a young scientist, is trying to find a serum capable of giving courage but he unwittingly invents a serum which transforms any man in a womanizer. His boss scents a good business and wants to produce the serum on industrial basis, but Roberto does not agree.
A cook from Sardinia who had emigrated to Milan goes back to his native island thinking he has inherited some money with his uncles death. He finds out he has to avenge his death instead.
Alberto Moretti arrives in Cortina D'Ampezzo, with daughter Marcella,who has just won a TV contest, the prize of which is a free stay in a luxury hotel.
A television broadcast launches a proclamation for amateurs: "If you know how to speak, you will know how to sing". The award mirage lured many person, with ambitions or financial problems, to enroll in the competition.
Two two-bit singers become thieves to make ends meet. One day during a theft in the house of a music impresario they hear Marco an electrician gifted with a beautiful voice and give him some money to help for his debut as a singer.
In the prison of San Vittore there is, among other detainees, a strange type that they call "Il Cavaliere". The latter suffers a conviction for theft and his fellow prisoners have a certain respect for him.
A woman has jumped or been pushed from five stories of an apartment house. The detective on the case lives there, and he discovers that the woman's estranged husband does also.
