A gangster, thief of atomic formulas, has a double in the person of a naive musician. A music hall artist who makes eyes at the musician is deceived by the gangster who also takes advantage of the resemblance to track down a band of thugs who are chasing him. Virtue is ultimately rewarded.

In a small town in the north of France, a family drama is born, develops and intensifies under the worried gaze of three children: little Zizi and her cousins ​​Albert and Quinquin.

Lily Ferronais can't stand her husband who, out of weakness, has let himself be led down the wrong road. She flees with her little Jeannette, whom she makes believe in the death of her father. Hired by the restaurateur Jean Garaud, the latter falls in love with her, to the chagrin of his mistress Hélène.

On the Franco-Belgian border, large and small traffickers engage in their illicit activities. For his part, a policeman is working to put an end to smuggling in the area.

Marguerite Le Goff has a sad destiny. Daughter-mother to a holidaymaker at the age of sixteen, she tried to earn a living in Nantes, but succumbed to the promises of the disreputable Pierre who had found her in a sailors' box. Deprived of her child, what would she do if good people didn't sympathize and her childhood friend Jean-Marie didn't take her with him?

At the Belgian border, a group of young people engaged in various contraband traffic bother the customs officers.

After his wife's death, a man discovers that his daughter may not be his.