After the Battle of Kalka, the threat of a Mongol invasion of Rus' passed. From now on, Russians and Mongols are friends. And now the Mongol hordes are galloping further to the west. And behind them march Russian regiments. What will be the response of knightly Europe? The sorcerer-mechanic Grigory Zabubenny, who was transported here from the twenty-first century, will see all this with his own eyes.