A file of signals intelligence reports, messages, and correspondence issued by the Government Code and Cypher School and sent by the head ('C') of the Secret Intelligence Service (MI6) to the Prime Minister, Winston Churchill. This file includes the following correspondence: from the Portuguese ambassador in London, describing negotiations with the U.K., on July 2; from the Turkish minister in Madrid, detailing German efforts to reach agreement with the Soviets, on July 1; from the Japanese ambassador in Kuibyshev, on a lecture at a local Communist Party branch, on June 28; the Japanese ambassador in Berlin forwards information from Hencke, on July 1; and SHARK: reporting success on June 27 and 28.