Barcelona, July 18, 1936. The winds of history change forever the life of young anarchist Valentina Mur. After her father dies on the day of a coup d'etat against the government of the Republic, she is driven to take part in the revolution exploding in the Catalan capital.
Valentina attracts the attention of charismatic young Communist Ramon Mercader, who, four years later and on the orders of the Soviet dictator Stalin, will assasinate the well-known politician Trotsky. However, she herself falls in love with Ramón's cousin, Artur Ramoneda, first-born son of a family of industrialists whom she meets on the day the young man is arrested for his presumed sympathy to the military uprising.