American reporter Keen Marlow is sent to Nazi Germany to report news other than what the government propaganda department releases. While investigating a prison, he is captured and tortured as a spy. Professor Eric Schmitt is thrown into the same cell with him for refusing to divulge his secret invention, a serum which he gives to Marlow before dying. With his strength enhanced by the serum, Marlow breaks out and creates the identity of the Destroyer, sabotaging Nazi activities and helping innocent Germans.; The Scar, a Nazi scientist, uses his death ray on Germans protesting food rations. A young woman named Florence von Banger runs up afterward to find her father among the dying, and swears that she will fight the Nazis to avenge him. The Destroyer hears her as he arrives on the scene, and offers to help her, revealing his identity to her. When they hear the Scar is about to use the ray again, the Destroyer goes to stop him even though they suspect it is a trap.; The Black Marvel's efforts to discover who killed a German scientist who had fled to the U.S. are complicated when one of his main suspects develops amnesia.; The Challenger issues a challenge to a serial strangler to strangle him while he walks unprotected through the city on the night of the next full moon.; The Blazing Skull is too late to stop German spies from informing their superiors of the Prime Minister's secret flight over their country, so he must go to Germany himself to stage a rescue.; When the miniaturized dead body of a general is delivered to the President as a doll, the Terror investigates the "Life-Like Doll Company" to prevent any more such bizarre murders.