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: an ULTRA/BONIFACE report for Wing Commander Spencer, an alias for the Prime Minister (PM); on the Mediterranean: of considerable troop reinforcements heading to Melos, on May 31; and on German Air Force (GAF) reconnaissance of the western Mediterranean, on May 27; the Brazilian chargé in Lisbon describes rumours about an Allied occupation of the Azores, on May 28; and a SUNSET intelligence summary to Washington, for June 1.