The turret fighter was predicted by many before World War II to be the only effective way of dealing with the new threat of the heavy bomber. In the event, a two-man fighter with its armament concentrated in a power-operated turret did not turn out to be the answer. The Boulton Paul Defiant and the Blackburn Roc were only two examples of the concept to enter service and only the Defiant was able to claim any success in combat. From the archives of Boulton Paul Aircraft, the company which built every single Defiant and Roc, come a host of photographs and testaments to the Defiant from those who built them and those who flew them.