The action takes place in 1714 in the London royal palace of St. James. The Duchess of Marlborough, the favorite of the weak-willed queen, skillfully rules the state. Her political opponent, former minister Lord Bolingbroke, dreaming of restoring his influence at court, successfully wages a cunning war against the duchess, using the rivalry between the queen and the duchess of Marlborough, who are in love with the young officer Mesham.