It is the year 1931. Future Red marshals and the remnants of horse-breeders of Tsarist Russia are improving the Oryol breed of racers. Large-scale selection is also being carried out by the state—through violence and hunger, through show trials and the capture of saboteurs—improving the Soviet “breed” of people. Investigator Zaitsev takes on a case about horses dying. But no longer as important is how he will find the criminal; the main thing is whom he will manage to push out from under the hooves of that terrible red horse during the investigation…