Michael Strogoff, captain of the army of the Russian Tsar Alexander II, is commanded to go from Moscow to Irkutsk, the capital of eastern Siberia, to inform the Grand Duke Dmitry, governor of the city and brother of the Tsar, that the Tatar army, led by Prince Feofar Khan, is moving to conquer the city and that he will have to resist as reinforcements will be sent to him. At the same time Ivan Ogareff, a Tartar who, after having served in the Russian army, was first exiled and subsequently tortured during his captivity, joins the Tartar army and embarks on the same journey to deliver, in the guise of a courier of the Tsar , a message to the Grand Duke, who is unable to communicate with Moscow, where it is written that the attack of the Tartars will come from a different direction than the one foreseen, in order to divide the Tsarist army and facilitate the conquest of Irkutsk, and in the mission is helped by Sangarre, a young Tartar who, by being courted by a Russian officer, allows Ogareff to kill him and wear his uniform and with whom he begins a love affair.