Russian mission of Antonio Possevino

Tsar Ivan the Terrible and the clever deacon Andrey Shchelkalov, seeing the inevitability of the defeat of the Russian kingdom in the Livonian War, send a message to Rome. In this message, the tsar asks the Roman pope to help establish peace with the Polish-Lithuanian Commonwealth, and in exchange promises to seriously consider the question of concluding a union, meaning the subordination of the Russian Orthodox Church to Rome. Of course, the promise is a diplomatic trick: the tsar does not need a union. However, in Rome, they do not suspect this, so a cunning and cruel Jesuit, Antonio Possevino, is sent to Moscow, who intends to achieve the conclusion of the union by any means necessary. Even if it means poisoning the metropolitan.