On 27 May 1942, SS General Reinhard Heydrich was assassinated by British-trained Czech agents who had parachuted into Czechoslovakia. He died of his wounds on 4 June 1942. Two days later, Gestapo Captain Horst Kopkow's department at Reich National Security HQ was given fresh directions. From 6 June 1942 until the end of the war, Kopkow was responsible for coordinating the fight against Soviet and British parachute agents dropped anywhere in Germany or German-occupied territories. This new direction for Kopkow made his name. Within months the "Rote Kapelle" Soviet espionage ring was uncovered in Belgium, who could be traced directly to Berlin and Paris. A new counter-espionage fight had begun, and any agents caught would pay with their lives. In France and Holland the Gestapo caught many Special Operations Executive agents trained in Britain. By spring 1944 almost 150 British agents had been caught and deported to German concentration camps, and almost all had been murdered without trial by the December. Kopkow was directly involved in these murders. Arrested by British forces after the war, Kopkow was extensively interrogated due to his counter-espionage experience.
For the next 20 years, Kopkow was a consultant for Britain's Secret Intelligence Service.