Plot synopsis: In the port of Havana, two biracial children, Mateo (Ricardo Román) and Caridad (Ninón Sevilla) grow up together. She is the daughter of a white man who died in a shipwreck and of a black laundress of African origin. Over the years, Mateo falls for Caridad, but she doesn't love him back because she has fallen for a Mexican captain, Martin (Pedro Armendáriz), who she happened to meet at the port. The captain also fell in love with Caridad and proposes that they live together and she accepts. Caridad works in a cabaret in the port and the owner, Guevara (René Cardona), feels an attraction for the girl, and in a moment of jealousy, tries to kill Martin. Martin falls into financial trouble and has to mortgage his boat to Guevara. When Martin returns to Veracruz, Mexico, Guevara feels that he's the new owner of Caridad.