California on the Amur

July 1885. Zagorsky and Gantszalin accompany the secret advisor S, who is traveling to the Far East on a diplomatic mission. On the way, they make a brief stop in Nizhny Novgorod, where a large annual fair is taking place. Zagorsky meets here with police officer Nikolai Nazarov, with whom he studied together in the cadet corps. Nazarov is monitoring the revolutionary Zabelin, hoping to expose a terrorist cell. However, on the day of Nazarov's meeting with Zagorsky, the revolutionary is killed. Judging by the gold coins found on the deceased, he was a distributor of counterfeit banknotes. Everything points to the fact that the suspected killer arrived from the Zheltuginskaya republic, or Amur California. Zagorsky and Gantszalin head to the placer mine to investigate the circumstances of the murder and the production of counterfeit gold coins.