During the Spanish colonization of Mexico, a time of duels with swords and witches' spells, a woman who is desired by all men wants only power and uses violence and crime to get it. She is condemned to death but gets a potion from a witch doctor that will make her look like she is dead. She reappears later as her own twin sister, recently arrived from Spain, and she uses all her powers of seduction to force a father and his son to face each other in mortal combat for the love of the devilish duchess.—Juve