Renato and Miro are black brothers raised by the family of the Caucasian Marta in an old mansion in Tijuca, Rio de Janeiro. Renato is graduated and has always looked for dignity, winning in life due to his honesty and search for social recognition.His brother, on the contrary, is a rebel small time crook and he says that his behavior is the fruit of the treatment he received while living in the Caucasian family's house. Their step sister Marta has a crush on Renato. When she meets the crook Walter Mendes, Marta falls in love for him. Renato argues with Walter, they fight, Walter tries to shoot Renato, but Renato accidentally kills him. However, Moleque Miro is blamed and wrongly sent to prison. Renato assumes his guilty, and the young boy Hélio, who witnessed the crime, convinces Marta to testify that Renato killed Walter in self-defense.