In 1941, Georgy Volkov, a captain in the State Security Service, is delivering to the Soviet Union a consignment of emeralds under a trade agreement between the USSR and Germany. Included in the shipment are a number of top secret documents, the value of which is far higher than any precious stones. The war begins, and the train on which Volkov is traveling is attacked by the Germans, and he must flee to the Soviet Union and deliver the important cargo. However, a dangerous enemy is hot on his heels - Abwehr agent Konrad von Bützow. The confrontation between these two strong, highly intelligent, and worthy opponents is the basis for the plot of the trilogy, "Spies Must Die!"