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 reports on the Mediterranean: that the German Air Force (GAF) are to jam RAF recce aircraft communications, on September 4; on Crete: a report on air defence deficiencies during an RAF attack on Heraklion of September 3; on the Southern Russian Front: of GAF operational orders; and a ground forces report for September 3; Naval Headlines; on North Africa: of GAF orders for an attack on aerodromes in Egypt on the night of August 30-31; with a query from the Prime Minister (PM); and the Chief of the Air Staff's (CAS's) reply.