Black Invaders establish secret base in the Rocky Mountains!... American H.Q. heard this news in surprise-and dread. Despite our vigilance, the enemy had penetrated our Border, were hidden in our very midst. What was their plan? How would they strike? The nation's safety depended on learning these answers in time-and Dusty Ayres and his buddies took the job, pitting their wings against the war's newest death weapon-the Blue Cyclone!