Together with a huge dowry, Sophia Paleologus, the royal heir of the Byzantine rulers, brought precious books to snow-covered Muscovy that were saved after the fall of Constantinople. The pearl of the collection, which became the basis for the famous library of Ivan the Terrible, was the so-called “Pigeon Book”. According to legend, she descended from heaven and was sent to earth by the Holy Spirit himself. It is not surprising that the minions of the Antichrist, a sect that called themselves the Illuminati, began hunting for the rare relic. Then, in the 16th century, Orthodox priests were able to bury the artifact from the forces of evil in a church monastery. But after five centuries, the divine book is again in danger. Supporters of the Evil One are scouring all over St. Petersburg in search of the relic. If it falls into their hands, then nothing will be able to save the sinful earth...