After Germany defeated France, Philby returned to Britain. Despite his previous membership in the pro-Fascist Anglo-German Fellowship as well as his wife's communist past, Philby was brought into the British Secret Intelligence Service in 1941 (he was aided by is father, who contacted Sir Stewart Menzies, the head of SIS, directly. As part of the counterespionage division of SIS, he he coordinated information exchanges between MI6 agents and Sandor Rado Soviet spy ring in Switzerland, obtaining valuable military information for Britain. Also was aligned closely with the Special Operations Executive, an espionage network which worked with underground resistance forces fighting against Germany. His success in these areas gained him high praise within the British intelligence community.
Was assigned, in October 1944, to Section IX of SIS, establishing an anti-communist desk. He was in charge of a movement to seek out communists in the British government, particularly those who had infiltrated British intelligence agencies. The basis for placing Philby in this position was his familiarity and friendliness with high-ranking Russian military and diplomatic officials. Philby's new Soviet handler was Anatoli Lebedev. Philby grew the section from a one man shop to a 30 person department in only 18 months. Worked hand in hand with William J. Donovan and Allen Dulles of the United States Office of Strategic Services, the predecessor of the Central Intelligence Agency.
