Alain is the only son of a wealthy bourgeois couple. He takes violin lessons in Ménilmontant, where he is spotted by Fleur, a poor girl: she is going to kidnap him and demand a ransom from the young man's parents, money which will be used to pay for a good lawyer for her brother accused of killing a policeman.
Fournier
Fleur
'La Puce'
Alain Leroy-Gomez
Mrs. Leroy-Gomez
Mr. Leroy-Gomez
Fleur's mother
Eliane Fournier
Woman who went mad
Young man
Pierrot
Julien
Arpia
Bourdieux
Norma
Blind man
Dédé, chauffeur
Man who shaves