The Justice league of America, and the Justice Society of America, prepare to test out their transmatters, devices which will allow both teams to bridge the dimensional void, between their respective worlds, at will. Seeing the transmatter as a way home, the Red Tornado begs to be sent back to Earth-2. The Green Lantern denies the Red Tornado's request. The transmatter is calibrated for lifeforms, of which the Red Tornado is not. The Green Lantern explains that the presence of the Red Tornado in the transmatter could be dangerous. Simultaneously, the Justice Society of America, and the Justice League of America, send three of their members through the transmatter. Neither group of heroes materialize at their proper destination.
The Red Tornado appears and reveals that, desperate to return to Earth-2, he stowed away, invisibly, inside the transmatter. His presence has caused the seven heroes to be shunted over to a different parallel world, Earth-X. Three Nazi tanks close on the Justice League of America, and the Justice Society of America. Doctor Fate conjures a mystic battering ram, only to have his attack go awry, felling the Golden Age Superman. The Nazi soldier are on the verge of defeat, when a single shot from their cerebro-gun drops the two teams of heroes. The Nazi solders move in to finish the heroes off, when the Freedom Fighters suddenly appear. After quashing the Nazi threat, the Freedom Fighters gather the fallen heroes, and take them to their hidden lair.
Uncle Sam explains the situation. The death of President Franklin Delano Roosevelt led to a shift in political power in the United States government. This rift allowed the Germans to develop the atomic bomb first. Since neither side was willing to use the weapon, World War II dragged on. During the course of the conflict, Plastic Man and the Blackhawks were killed. In 1968, German scientists invented a weapon that could enslave the minds of entire nations. At that point, Germany had won the war. Only a few pockets of resistance remained to carry on the fight. At Doctor Fate's request, the Freedom Fighters introduce themselves, and reveal their origins. Doctor Fate uses a crystal ball to discern the locations of Germany's mind control weapons.
The three teams split into three strike forces, to destroy the weapons. The Red Tornado is left behind to co-ordinate the team's efforts. Doctor Fate teleports the three teams to their destinations. The Batman, Doctor Fate, the Human Bomb, and the Ray appear in Nazi-occupied France. Specifically, at the base of the Eiffel Tower, in Paris. The Ray travels up a spotlight, to the top of the tower, to take out the watchmen. One of the soldiers manages to hit the panic button, calling for re-enforcements. The Ray is overwhelmed by the Nazi soldiers. The Batman, Doctor Fate, and the Human Bomb come to the Ray's rescue. The Human Bomb destroys the final barrier to the mind control machine. Astonishingly, the mind control weapon is an enormous robot.
To defend itself, the robot analyzes the four heroes, then creates beings specifically designed to counter each individual hero's abilities. To defeat their adversaries, the heroes merely switch targets. Doctor Fate destroys the Human Bomb's foe. The Human Bomb destroys the Ray's foe. The Ray destroys the Batman's foe. The Batman destroys Doctor Fate's foe. The robot ramps up it's mind control power, to enslave the four heroes. Though their minds are under the sway of the robot, the heroes, by reflex alone, complete their mission to destroy the mind control device. Paris is liberated. Conferring with the Golden Age Flash, the Green Lantern voices his fears that their comrades died, traveling through the transmatter.