1237 year from the birth of Christ. No one still believes that war with the Tatars in Rus' is approaching. The princes indulge in civil strife. Merchants trade, boyars feast. And only Kondrat Zarubin, whose spirit, by the will of fate, was transferred to the body of the Ryazan boyar Evpatiy Kolovrat, tries to do something. Knowing about the impending threat, Kolovrat convinces the Ryazan prince Yuri Igorevich to prepare the city for defense and teach the army to fight in a new way so as not to lose the battle with the steppes who have already captured half the world. And also - to arm the warriors with hitherto unknown weapons. A mortal threat is inevitably approaching. And now the army of Khan Batu set up camp on Voronezh. Trouble is brewing along the borders of the principality, and confusion is growing in Ryazan itself. Nobody knows when the invasion will begin. Nobody believes that it is possible to defeat Batu's hordes. And only Kolovrat understands how to change fate.