Final installment in Juan Orol's Percal trilogy. In this film, Malena is freed from prison by a gangster but a rival mobster will make things impossible for them.

Gangster Johnny Carmenta must confront the "Charro of the Slums" Pancho Domínguez, who has control over the city, but their rivalry gets worse when rumba dancer Rosa befriends both men.

After listening to the waltz "Carmelita", dedicated to his wife, President Diaz instructs Don Susanito seeking the composer Chucho Flores to give her a piano. Don Susanito located Chucho, a bohemian who lives drunk and surrounded by poets and artists. Don Susanito was named patron protector of artists and aspiring young stars of the stage, which leads to a series of adventures in the middle of songs, dances and loves.

A dedicated wife and mother takes the blame for embezzling money that was actually stolen by her husband in order to buy medicine and a doctor's care for the couple's seriously ill infant son. Consequently, the well-meaning woman is willingly sentenced to years in prison for a crime she did not commit-all because she believes her son will fare better if the bond between father and son remains intact. Upon her release, she soon discovers that no good deed goes unpunished. Her once loving husband has remarried a woman that her son calls Mother, After just a brief glimpse of her loved ones, she simply leaves without saying a word. Many years later, she becomes a patient at her son's busy medical practice just so that she can keep an eye on his progress in secret. In a cruel twist of fate, it is only after he diagnoses her as being terminally ill does does she reveal her true identity. The poor woman subsequently learns that her former father-in-law lied about her initial release from ...