In late spring 1940, Nazi Germany's domination of Europe had looked unstoppable. With the British Isles in easy reach since the fall of France, Adolf Hitler was convinced that Great Britain would be defeated in the skies over her southern coast, confident his Messerschmitts and Heinkels would outclass anything the Royal Air Force threw at them. What Hitler hadn't planned for was the agility and resilience of a marvel of British engineering that would quickly pass into legend - the Spitfire.