Following the Empress’ death, Pyotr has become Emperor of Russia. Ekaterina, the woman who warned the Four Musketeers, steals the throne back from him with their help. The Four Musketeers continue to battle members of the Revolutionary Brethren.

D’Eon’s battle against Vorontsov is finally finished, with Lia dealing the final blow. The Four Musketeers follow Robespierre to London.

The Four Musketeers meet with the French Ambassador to England, and they attend a party thrown by the English king and queen intending to steal important documents held by the British Undersecretary of Foreign Affairs.