Exactly a century ago, intelligence agencies across Europe first became aware of a fanatical German nationalist whose political party was rapidly gathering momentum. His name was Adolf Hitler. From 1933, these spy services watched with growing alarm as they tried to determine what sort of threat Hitler's regime would now pose to the rest of Europe. Would Germany rearm, either covertly or in open defiance of the outside world? Would Hitler turn his attention eastwards - or ...

Exactly a century ago, intelligence agencies across Europe first became aware of a fanatical German nationalist whose political party was rapidly gathering momentum. His name was Adolf Hitler.From 1933, these spy services watched with growing alarm as they tried to determine what sort of threat Hitler's regime would now pose to the rest of Europe. Despite intense rivalry and mistrust between them, the spy chiefs began to liaise and close ranks against Nazi Germany....