The year is 1440; nine years have elapsed since Jeanne d'Arc's execution in Rouen, and the Hundred Years' War has entered its final stages. Driven by greed, the French nobility rises up against King Charles VII, seeking to reclaim feudal authority and block his centralizing reforms. Although they were once united in fighting the English, the nobles have now turned on the crown, risking a return to the war from which France had just begun to emerge. Emily du May, the illegitimate daughter of a French duke, is adopted by Robert de Baudricourt and raised as "Emil"—presented as a male, just as he had done for the late Jeanne. When Robert is called by Constable Richemont to combat the rebels, Emil confronts her foster father and insists on joining the French loyalists. Guided by visions of Jeanne, Emil remains determined to complete her predecessor's mission. As she strives to halt the rebel forces commanded by Dauphin Louis, the ambitious son of Charles VII, Emil encounters the agents of the rebellion and travels across the nation Jeanne had aimed to unite.