A file of correspondence and memoranda covering the exchanging of intelligence between Britain and the U.S.S.R. during the Second World War. The file includes Russian requests for meteorological intelligence and information on German air force call signs, as well as British discussion of whether they should inform the Russians that their codes had been broken by the Germans. The bulk of the file is made up of a discussion of an attempted cooperation between the Secret Intelligence Service (MI6) and the Soviet NKVD, in which the Soviets attempted to exchange information for the release of members of the Indian independence movement in captivity in India, who they wished to use as agents against the German intelligence network in Kabul.