Alternative history, 16th century. The main character saved the first-born son of Ivan IV. With the money received from the sovereign, the prisoner built the first metallurgical plant in Russia, where he began producing what was then the most advanced artillery and revolving rifles. The following year, he organized an expedition to the Sok River, where he founded the first Russian fort in the lower reaches of the Volga. The main character, using the sovereign's charter, began the development of Kama copper, Baskunchak and Elton salt, as well as the Vodinsky sulfur deposit. By the spring of 1555, a lot had been done. Free-floating horse-drawn vessels were built, and the first apiaries were created. The production of unicorns, cast-iron grapeshot for them and high-quality black powder has been established, a murderous surprise has been prepared for the Crimean Tatars near Sudbyshchi, the Swedish king Gustav Vasa, his son Johan III, who never managed to become the Duke of Finland in this story, was captured in Vyborg, as well as commander of the Swedish squadron Jacob Bagge. History has begun to change... What's next?