Codebreakers and Spies tells the astonishing story of how Britain's intelligence operatives, experts and special operations teams contributed to the Allies' victory in the Second World War. The work of the Bletchley Park codebreakers in breaking the German Enigma cipher is estimated to have cut the length of the war by around two years, saving countless lives, while the Double Cross system, in which German secret agents were 'turned' by the British to feed their Nazi agent-runners with false information, ensured the success of the D-Day landings.

Codebreakers and Spies not only reveals new details about these remarkable operations but also tells the compelling story of how MI6 turned the disaster of lost networks across Europe into triumph. The stories range from extraordinarily courageous to bizarre, with desperation driving the intelligence services to recruit astrologers and even a stage magician to help retrieve intelligence and allied aircrew from of Nazi-occupied Europe. Intelligence historian Michael Smith thrillingly recounts the daring and often moving lives of the heroes and heroines who risked their lives for victory.