Chekist Olga Anisimova, who infiltrated the White Guard center in Harbin, and border guard Aleksei Mogilov prevent a number of provocations on the Chinese Eastern Railway, uncovering a conspiracy between the White Chinese and the White Guard center in Harbin.

On instructions from Polish intelligence, a group of bandits dress up in Red Army uniforms and attack a Soviet border town.

Alan York is a race horse jockey who sees his friend and chief rival jockey fall to his death during a steeplechase race. Alan knows it could not have been an accident. He pursues clues while meeting a lovely young lady and her fascinating uncle, until he finally discovers why his friend died... and why he is next to die.