A comet over Europe in 1618 opens this account of the Thirty Years' War, which the film traces from a religious revolt in Prague to a continent-wide conflict that killed roughly a third of Germany's population. The narrative leans on the diary of mercenary Peter Hagendorf, one of the rare surviving first-person accounts of a common soldier's war, and the letters of Princess Elizabeth Stuart, whose family's fortunes were tangled up in the fighting from the start. The film tracks how the war shifted from armies of medieval knights to gunpowder warfare fought by mercenary companies, and how a conflict that began over faith hardened into a struggle among states for territory and power. Historians and battlefield detail carry the story from the Defenestration of Prague through the war's spread across the German lands, ending with a Europe whose political map had been redrawn by the time the fighting stopped. History Hit produces the film with narration, maps, and period sources doing the explanatory work throughout.