Innumerable books have been published on the two most famous fighter aircraft of all time, the Supermarine Spitfire and the Messerschmitt Bf109. But books setting out to tell the story of both aircraft are very much rarer - probably fewer than the fingers of one hand. Yet their joint story is one which bears retelling since both were essential to the air campaigns of World War Two. Incredibly, the men who designed them lacked any experience...