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 messages: a reply to the Prime Minister's (PM's) query regarding the form in which information that German Army reserves on the central Russian Front were reduced to one division, was passed on; and a reply to a query regarding the strength of a fighter group.