From 1931 and for nearly a decade, French intelligence had an agent operating within Hitler’s inner circle. He provided France with the secrets of Enigma, as well as advance warning of the invasions of the Sudetenland, Czechoslovakia, Poland, and eventually France.

Yet neither the French political leadership nor the military acted on his intelligence. Churchill, however, understood its value and put it to use.

This documentary revisits the story of one of the most important, and least known, spies of the Second World War.