Two agents - ethnographer Leonard Kalganov and paleopsychologist Berg, observer-scientists from the Ambassadorial Corps, were abandoned on the terrestrial planet Soler and were left without communication with their colleagues, since the interdimensional tunnels were completely clogged due to a supernova explosion nearby. The mission of the Earth’s representatives on such planets is to, through their constant presence (sometimes for many centuries), accustom the aborigines to the idea of the existence of other worlds, to prepare and adapt them to future contact of civilizations. Among the inhabitants of the Middle Counties, where observers impersonating themselves have settled for the ambassadors of the mythical overseas Terra - the Middle Ages both in the yard and in their heads. At first, the aborigines appear to the imaginary Terran ambassadors to be completely harmless, the local rulers to be extremely fair, and the curious local binary religion to be quite tolerant. But the cloudless idyll does not last long. Ominous events begin, accompanied by unprecedented natural disasters. Earthlings are drawn into a cycle of palace secrets and coups. Will agents Leon and Berg be able to help their neighbors in the face of impending chaos - or will their intervention only plunge Soler into the abyss of bloody wars and terrible epidemics?..