The members of a Buenos Aires family have three hobbies — "berretines" in Buenos Aires slang — that keep them apart of their duties. Because of that, the family business is going down, and the only one who is concerned is the father, who hopes for his fourth son, an architect, to save the situation.

A delinquent, the son of a police commissioner, leaves prison to seduce someone who should be like a sister to him: a girl raised and loved by his parents. To force her to give in to his obsession, he kidnaps her little daughter.