In June 1940, Britain stood alone against the Nazis. Hitler was convinced that it was only a matter of days before it sued for peace. He had more troops, a better air force and the better weapons. This film shows how close Britain came to defeat, as its exhausted air force struggled to fight all the German Luftwaffe. However, because of critical errors by the Luftwaffe commander Hermann Goering, Britain was able to regroup. Then using its brilliant team of code crackers and specially trained spies, it began the fightback, working alongside the resistance movements in the occupied territories.
Some just counted tanks, others stole blueprints for bombs. The Cold War was the battleground for thousands of spies and spotters. Even the Allied Military Missions in Germany doubled as covert observers in the spying game.