In 13th-century Bohemia, King Přemysl Otakar II sends his Bezděz castle steward Oldřich of Chlum north to broker a peace-marriage between the feuding Dubé and Vartemberk houses, only for him and his men to stumble on a murdered merchant’s trail. At the celebratory feast meant to seal the alliance, the Vartemberk castellan is killed and suspicion falls on a humble lutenist whose fiancée the victim had tried to violate, plunging Oldřich into a dangerous game of courtly intrigue.