With its back against the wall in the summer of 1940 methods to hit back at the Germans occupying Europe were urgently sought. The Special Operations Executive was created to operate as a secret army, able to send operatives into Europe and to fight behind enemy lines. Their role encompassed espionage, sabotage and reconnaissance. They were also key in helping to establish resistance networks in occupied countries - most notably in France in preparation for D-Day. The location of their headquarters led to them being known as "the Baker Street Irregulars" and they attracted recruits from the professional classe including lawyers, bankers, secretaries and even housewives. Another rich source was the First Aid Nursing Yeomanry.