April 1945. The Nazis are mass-producing battle mecha and are almost ready to deploy them. The Americans are ready to deploy a doomsday bomb. Kishin Corps has completed Kishin model 4, the biggest, baddest mecha ever seen, but can't deploy it yet.

The Kanto army's control module has been stolen. The Nazis have captured Maria Braun and now Kanto forces badly want to steal the Nazi mecha. Meanwhile the aliens have possessed Nazi leader Colonel Lingelle.

Situations like this call for immense quantities of violence.

"Youth" delivers immense quantities of violence. Kishin Corps can't unleash the Kishin 4 until they recapture the missing control module; but circumstance forces them to action when they discover the location of the island base whereon the Nazis and aliens are collaborating to build a mecha army. In addition, they learn that an American plane currently over the Atlantic carries Einstein's bomb. The Kishin army mobilizes to save the world from evil and from the nightmare of technology out of control.

By train, plane, glider, tank and foot they storm the island stronghold. With cannons, bombs, traps and fire the Nazis resist. The sky splits open and aliens descend from a brimstone-belching vortex. The island crumbles revealing an alien mother-blob beneath which emits laser-firing aliens into the maelstrom. Maria risks death to bring Taishi the control module he needs. Colonel Shinkai steals the Panzer Knight he adores. The sky burns, the earth trembles, guns blaze, armies collide and Taishi battles Shinkai to avenge his father and save the world.

Then the bomb arrives.

Adventure stories, particularly those set in wars, inevitably must end with a really big fight. When character arcs and moral themes have been woven into an adventure saga, a key challenge is to construct the story so that the characters' arcs and the thematic questions can conclude satisfactorily with a really big fight. "Geo-Armor" rises to this challenge.

In episode five Eva Braun spoke of the specter of Einstein's bomb (which, though referred to as an anti-alien bomb, is explicitly an atomic bomb since Einstein explains it by writing E=mc²) saying it could, "Make scientists the enemies of humanity." At the start of episode seven, Kishin Corps learns that the bomb is only 30 minutes away. If they cannot defeat the Nazi/alien alliance before the Americans arrive with, "Glamour Girl" (the bomb's name bitingly parodies the hauntingly whimsical titles Fat Man and Little Boy, the names of the bombs dropped on Hiroshima and Nagasaki), any hope of a future wherein science serves the interests of humanity will be eradicated. On the other hand, if the Nazis and aliens defeat Kishin Corps, the human race may be eradicated.

Not only the fate of the world, but the culmination of every individual character's ambitions hinges upon the outcome of the final battle. If Nazi Colonel Lingelle succeeds in deploying a mecha army, he may personally take over the Reich. If Shinkai succeeds in stealing the mecha technology, he hopes to take over the Kanto army. Eva Braun has devoted her life to developing mecha technology, which will be tested in this battle. Maria Braun has devoted her life to give Taishi and the other orphans and children a better future. Every thread of the plot and every aim of the characters lead inexorably to, and depend entirely upon, the battle.

On the eve of the final battle Taishi recalls his father's dying words, "It's up to your generation now," and wonders just who and what his generation is. He also recalls his father saying, "There are a lot of ways to use something and the way things get used depends completely on the person using them."

Since Taishi has been chosen to pilot the new mega-mecha Kishin 4, these sentiments weigh heavily upon him. As the chosen avatar of his generation and his cause, Taishi alone will have to control the summa of technological might in order to complete the quest his father left to him.

Taishi's personal challenge - to use immense power wisely and nobly - distills "Geo-Armor's" debate about technological ethics into its essence. Technology has no morality, only power. It will only serve as a positive force in the world if the generation that inherits it can control its power with their virtue. If spectacularly kicking huge amounts of Nazi, alien and Kanto ass - and saving the world from near Armageddon - counts as wise and noble, then Taishi acquits himself well in this regard.

Minor characters each face their own moral choices throughout the final episodes. Lt. Fujishima of the Kanto army chooses to betray the Nazi/alien axis and abandon her hopes that her evil allies would aide her nationalist agenda. She fights to aide humanity instead. Jack - Taishi's onetime friend, then rival - chooses to join Kishin Corps and forgive past resentments. Meanwhile Lingelle and Shinkai, thirsting for individual power, give themselves over to the aliens, and to the thrall of the modules. Each choice is a microcosm of the central theme dramatized in Taishi's actions. Those actions illustrate the overt moral of "Geo-Armor." Only through responsible use of science, technology and power in the service of humanity, and not nations or individuals, can disaster, specifically a nuclear holocaust, be avoided.