Writer and philosopher Voltaire, loyal to his king, Louis XV of France, nonetheless writes scathingly of the king's disdain for the rights and needs of his people. Louis admires Voltaire but is increasingly influenced against him by his minister, the Count de Sarnac. Louis's mistress, the courtesan Madame de Pompadour, is Voltaire's protector and advocate, but even she has difficulty preserving his welfare when Voltaire publicly excoriates the king for the wrongful execution of one of his subjects, Calas. Voltaire gives refuge to Calas's daughter and endeavors to show the king the error of his ways. But the Count de Sarnac, with an agenda of intrigue and disloyalty, determines to do away with the troublesome Voltaire.