Fate sometimes takes completely unexpected turns. The young scientist Fyodor Shergin, having experienced another creative crisis and a streak of failures, leaves on the advice of his loved ones to the homeland of his ancestors - Altai. Hoping to unwind and relax, Fyodor, against his will, finds himself drawn into a cycle of strange events: a night assassination attempt on a train, a mysterious fellow traveler, and finally, participation in the investigation of a century-old Siberian mystery connected with his legendary great-grandfather, a white officer who participated in a secret operation to save the royal family. , and the search for the mysterious Altai Golden Horde...