en Cuevana 3. In 1889, mounted on a small gray horse named Serko, Dimitri leaves his garrison on the Asian borders of the Russian Empire on the banks of the Amur River. After extraordinary adventures, they both arrive in St. Petersburg, at the court of the Tsar. Having covered more than 9000 kilometers in less than 200 days, this young rider has achieved the most fantastic equestrian feat of all time.