Visiting a boarding school for girls, married Tsar Alexander II gets to know the defiant Princess Katya Dolgoruky and falls in love with her. He invites her to the court ball at his winter palace, where he dances the first dance with her. To escape the court gossip about their affair --- for their love to one another is no longer a secret --- the Tsar sends his beloved to France to complete her studies. At the World's Fair in Paris in 1869, where the Tsar is to be received by Emperor Napoleon III, the ruler of all the Russias barely escapes being assassinated. Katya witnesses the near-tragedy and the two swear to one another never again to be apart from each other. Alexander takes the girl back to St. Petersburg, where she becomes a lady-in-waiting to Alexander's wife and will later marry him. Again and again, there are attempts on the lives of the couple. The Tsar, however, is attempting to bring justice and freedom to his subjects through a new constitution; but before he can do this, he'll finally be taken down in the next assassination attempt.

Saint-Pétersbourg, 1865 : au milieu du siècle dernier, la Russie est gouvernée par le tsar Alexandre II qui est entré dans l’histoire comme le « tsar libérateur » (il a aboli en effet le servage). En visitant un internat de jeunes filles Alexandre II rencontre Katja Dolgoruki, une princesse à l’allure rebelle, et tombe amoureux d’elle alors qu’il est marié. Il l’invite au bal de la cour dans son palais d’hiver, où il ouvre le bal en dansant avec elle. Pour éviter les discussions à la cour, parce que leur amour n’est plus un secret, il envoie Katja en France un certain temps.