Torrington Base
The assault carrier Albion arrives at an Earth Federation base in Torrington, Australia, bringing with it a pair of new Gundam mobile suits developed by the civilian company Anaheim Electronics. However, the Albion's arrival has been anticipated by renegade soldiers of the Principality of Zeon. Just after the Gundam GP02A is loaded with a live nuclear warhead from Torrington's arsenal, the Zeon ace pilot Anavel Gato seizes the mobile suit and flees the base.

A young test pilot named Kou Uraki takes the controls of the Gundam GP01 and sets out in pursuit of the stolen machine. With the help of his comrades South Burning and Chuck Keith, and the support of Anaheim engineer Nina Purpleton, Kou prevents Gato from escaping into space, only to see him make his getaway by sea instead.

Pursuit
Kou and his friends are transferred to the Albion, which is now assigned to recapture the stolen Gundam and its devastating warhead. The ship makes its way to Eastern Africa, where Gato has made contact with a group of Zeon renegades whose HLV capsule can carry the Gundam GP02A into orbit. Gato's allies attack the Albion to buy time for his escape, forcing Kou and his comrades to continue their pursuit into space.

Gato returns to the Zeon renegades' hidden headquarters and presents the captured Gundam to rebel leader Aiguille Delaz. As Delaz broadcasts a declaration of war against the Earth Federation, the pursuing Albion is intercepted by the forces of Delaz's new ally, the sinister Cima Garahau. Kou ignores Nina's warnings and takes the improperly configured Gundam GP01 into space combat, where it is all but destroyed at Cima's hands.

Von Braun City
The Albion retreats to the lunar city of Von Braun, where the wrecked Gundam GP01 is returned to Anaheim for repair and reconfiguration. Kou, humiliated by his defeat, leaves the ship and meets a gruff Zeon veteran named Kelly Layzner. After helping Kelly reconstruct his prize possession, a vintage mobile armor left over from the One Year War, Kou returns to the Albion with renewed confidence. But before he leaves the moon, Kou will meet Kelly again, and this time in battle.