In 1437, after years of regency, the pious and gentle Henry VI, the Lamb, comes of age and accedes to the English throne. His poor health and frailty of mind render him a weakling king; Henry depends on his closest men, Spymaster Derry Brewer and William de la Pole, Duke of Suffolk, to run his kingdom. With England's territories in France under threat, and rumours of revolt at home, fears grow that Henry and his advisers will see the country slide into ruin. With a secret deal struck for Henry to marry a young French noblewoman, Margaret of Anjou, those fears become all too real.