Kang the Conqueror has devised the means to destroy the Avengers. He theorizes that foiling the plans of the World War I fighting ace, the Phantom Eagle, of destroying the German super gun (which if allowed to go on unopposed would change the course of the first world war and of history) would mean removing the Hulk, and the Avengers from existence.
Kang attempts to go back in time, but he is thwarted by a time storm. So Kang selects the Hulk to travel in time since only one as he could withstand the perils of the time storm.
The villain snatches the Hulk from his own time and tricks him into believing that if he stops the Phantom Eagle, it will stop Bruce Banner as well. The Hulk accepts and gets sent back in time, easily withstanding the trauma of the time storm.
Hulk finds himself in France during World War I surrounded by German soldiers who attack him. After defeating them, he makes his way to the powerful weapon and prevents the Phantom Eagle from dropping his bomb into the barrel of the supergun. Done with that, antiaircraft fire hits accidentally Hulk leaps at the Phantom Eagle’s plane from the Germans.
Thinking the Germans attacked him, Hulk turns his attention to them. So they fire the super gun at the Hulk, which does not even slow him down! In his rage, the monster destroys the weapon, thwarting Kang’s plans.
Kang leaves the Hulk in that time period, but the effects of the time storm force the Hulk back into his own time, and thrusts Kang out of his own. Thus, Hulk returns to the present and transforms into Bruce Banner, while Kang gets trapped in a limbo.
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