M16 has been cloaked in secrecy and shrouded in myth since it was created a hundred years ago. Our understanding of what it is to be a spy has been largely defined by the fictional worlds of Ian Fleming and John le Carre. Gordon Corera provides a unique and unprecedented insight into this secret world and the reality that lies behind the fiction. He tells the story of how the secret service has changed since the end of the Second World War and, by focusing on the people and the relationships that lie at the heart of espionage, illustrates the danger, the drama, the intrigue, the moral ambiguities and the occasional comedy that come with working for British intelligence.