Daichi, the son of a former astronaut who gave his life to defend Earth, finds himself in the same situation after returning to the island of his youth.

Daichi learns more about his father's demise, and meets up with familiar childhood friends as his unplanned space mission comes to an end.

The hacker who helped Daichi on his first mission introduces herself as Magical Girl Akari, daughter of the commander. Later, the same Kiltgang who killed Daichi's father launches toward Earth, giving Salty Dog a good opportunity to put Daichi in harm's way.

Teppei is brought in for evaluation after suddenly summoning a Kitlgang to save Daichi. While Hana is being looked at, Daichi and Akari head to town and run into the Kiltgang operators from the moon, now earthborne and ready to start trouble.

Teppei is sent on a secret mission to retrieve a mysterious man named Eiji Arashi. With Akari in tow, they attempt to wake him from hypersleep before a group of mercenaries get to him first.

The Kivoto's Plan is the last resort for Earth - jettison it's most important humans and let the Kiltgang devour the rest left behind in order to make them move on. With both opposing factions considering such a dangerous solution, the danger looms ever closer.