GCHQ

As we become ever-more aware of how our governments “eavesdrop” on our conversations, here is a gripping exploration of this unknown realm of the British secret service: Government Communication Headquarters (GCHQ). GCHQ is the successor to the famous Bletchley Park wartime code-breaking organisation and is the largest and most secretive intelligence organisation in the country. During the war, it commanded more staff than MI5 and MI6 combined and has produced a number of intelligence triumphs a