Based on the tale by Gustavo Adolfo Bécquer (a Spanish romantic author), the film tells the story of two knights, a lady, and a mystery. Set in 13th-century Toledo, the two friends, Lope Sandoval and Alonso de Carrillo, engage in a deadly duel at midnight for the love of Inés de Tordesillas. The darkness that surrounds them in the forest is almost absolute, with only the light of a lantern illuminating the fight. Supernatural forces and inexplicable events will determine the fate of those involved in a night of horror, where the best and worst of human nature converge.