The film, based on Eric Jager's book The Last Duel: A True Story of Crime, Scandal and Trial by Combat in Medieval France, recounts the real-life revenge drama surrounding the last legally sanctioned duel in France. It follows a man who goes to war and returns to discover a friend has raped his wife. When no one will believe the woman, the soldier appeals to the king, asking that he be allowed to fight a duel to the death to decide the man’s fate.