The mid-16th century. In Tver, a cache is found containing, among other treasures, the famous icon of the Mother of God, brought from Athos and missing since the uprising of 1327. The ruler orders that the shrine be delivered to Moscow… However, not everyone agrees with the tsar’s decree. The Tver nobleman Voronov believes that it is Tver, not Moscow, that should possess the wonder-working icon. He convinces bold men to rob the tsar’s convoy. Once the loot is seized, the criminals hide in a swamp. The task of returning the missing relic is assigned to a special detachment of selected fighters under the command of Prince Dmitry Saveliev. But at the last moment, the prince’s plans become known to the enemy…