In 1278, on the plain of Marchfeld east of Vienna, Rudolph of Habsburg faced Ottokar II of Bohemia in a battle that had been building for five years between two rulers who could not both hold power in Central Europe. The film traces how Rudolph's victory broke the Přemyslid dynasty's dominance and set the Habsburgs on a path that would shape European politics for centuries afterward. Archaeologists and historians walk the battlefield itself, explaining why a clash of this scale left so few physical traces in the soil, and describe the modern surveying and detection methods now being used to locate weapons, armor fragments, and mass grave sites that could confirm troop movements described in medieval chronicles. Maps and reenactment imagery help track the cavalry charges and shifting alliances that decided the fight. The result is a close look at how a single afternoon of combat rearranged the balance of power in the German-speaking world, and at the slow archaeological work of proving it happened the way the histories say.