On 9 November 1939, two unsuspecting British agents of the Special Intelligence Services walked into a trap set by German Spymaster Reinhard Heydrich. Believing that they were meeting a dissident German general for talks about helping German military opposition to bring down Hitler and end the war, they were instead taken captive in the Dutch village of Venlo and whisked away to Germany for interrogation by the Gestapo. The incident was a huge embarrassment for the Dutch government and provided the Germans with significant intelligence about SIS operations throughout Europe. The incident itself was an intelligence catastrophe but it also acts as a prism through which a number of other important narrative strands pass. Fundamental to the subterfuge perpetrated at Venlo were unsubstantiated but insistent rumours of high-ranking Germany generals plotting to overthrow the Nazi regime from within. After the humiliation suffered when Hitler tore up the Munich Agreement, British Prime Minister Neville Chamberlain was anxious to see just how much truth there was in these stories; keen to rehabilitate his reputation through one last effort to find a peaceful rapprochement with Germany. When Franz Fischer, a small-time petty crook and agent provocateur, persuaded British SIS operatives in the Netherlands that he could act as a go-between for the British government with disaffected German generals, the German Security chief Reinhard Heydrich stepped in and quietly took control of the operation. Heydrich’s boss, head of the Gestapo Heinrich Himmler, was anxious to explore the possibility of peace negotiations with Britain and saw an opportunity to exploit the situation for his personal benefit.On the day before a crucial meeting of conspirators and British agents on the Dutch-German border, a bomb exploded in the Bürgerbräukeller in Munich in the exact spot where Hitler had stood to deliver a speech only minutes earlier. The perpetrator was quickly arrested, and Hitler demanded that Himmler find evidence to show that the two events were intimately connected—the British agents were snatched hours later. While the world was coming to terms with the fearsome power of German military might the British intelligence capability in northern Europe was consigned to the dustbin in the sleepy Dutch town of Venlo. This first full account of the Venlo incident explores the wider context of this German intelligence coup, and its consequences.