In 16th century Mexico, an Indian and Spanish woman named Luisa is visited by an upper class Spanish conquistador named Don Nuño de Montesclaros (Eduardo Farjado). She falls in love with the man so much so that she leaves her life to start anew with Don Nuño. Don Nuño and Luisia have a boy and girl. However, Don Nuño leaves, as he must go on missions. Days later she is visited by one of Nuño's fellow conquistadors. He tells her that Don Nuño will not return home for a long time due to his duties. Suspicious, she follows the conquistador and comes to a palace where she finds Don Nuño. He explains that he will marry a new woman since Luisa is not fully Spanish. Enraged and heartbroken, she curses Don Nuño and his descendants that all his bloodline's firstborn will be murdered violently. When she returns home, she stabs her own children to death. The entire town finds out and Luisa is sentenced to death.