Famed Spanish fencing master Don Jaime Astarloa (Omero Antonutti) teaches his art to a dwindling number of interested students. When the talented Adela de Otero (Assumpta Serna) demonstrates her formidable skill and expresses her desire to become his first female apprentice, Astarloa cautiously agrees. After a few lessons, de Otero asks her new master to share his most cherished secret -- the method behind an unstoppable fencing maneuver guaranteed to end in any opponent's death.