During the second world war, the special operations executive, a british intelligence agency, recruited agents to conduct sabotage and espionage in nazi-occupied france. Among these agents was henri dericourt, a pilot who was tasked with organizing the transport of agents and equipment into and out of the country. However, dericourt's activities were compromised by his secret connections to the gestapo, the nazi secret police, and the british secret intelligence service, also known as sis. This led to the destruction of the prosper network, one of the largest resistance networks in france, and the arrest of hundreds of its members. The story of dericourt's double, or perhaps triple, agent status remains one of the most controversial and mysterious episodes of the war.