A drifter lands a job as an officer in México City's elite motorcycle police unit and gets home with a mate of this unit. The mate is in love with a girl, but he and she are always making jealous to each other. The drifter and the mate get involved themselves in a fight to become the winner of conquering ladies and performing unit acrobatic tricks, interfering with their friendship and profession.

1949 film by Ismael Rodríguez

Two kids take a book from a trash can. They begin to read the story of a poor neighborhood in Mexico City. Carpenter Pepe "El Toro" (Infante) lives with his daughter Chachita (Munoz) and woos pretty "Chorreada" (Pavon). Around them, a group of fellows live their lives in many ways: a pair of always-drunk women known as "La Tostada" (The Toast) and "La Guayaba" (The Guava); a beautiful woman (Jurado) who always oversleeps; a hooker with pneumonia (La Tisica) with a dark past. Tragedy comes when Pepe is falsely accused of robbery and sent to the jail.