After WWII, many of the men and women who had worked at Bletchley Park moved on to GCHQ, the British government's new facility, established to fight a new foe - Stalin's KGB. Sinclair McKay has interviewed various members of this secret organisation, from codebreakers to radio listeners to mechanical engineers and computer programmers, who all shared the common desire to build a new Britain and protect it throughout the Cold War. His book on the subject is: 'The Spies of Winter: The GCHQ Codebreakers Who Fought the Cold War'.