The Robot Research Club is shocked to hear that not only has Doc been rushed to the hospital, but he's also considering closing his shop. Junna tries to encourage him to keep the shop open, but her fear of robots makes it difficult. 

At last, the Robot Research Club enters the ROBO-ONE tournament! The revolutionary KILL-BALLAD control scheme makes Kaito a force to be reckoned with, but will it be enough to win the tournament and save the club?

Kaito and Junna set out to investigate the strange "ghost" that Kaito caught a glimpse of... but only succeed in discovering more mysteries.

While Kaito and friends encounter more mysterious phenomena, another solar storm suddenly hits the Earth. Meanwhile, Akiho gets the GunBuild-1 project funded and rolling full-steam ahead!

After the accident with GunBuild-2, the school's vice principal shuts down the Robot Research Club for good and orders that all of the club's robots be dismantled.

At last, the big robot expo in Tokyo gets underway! The diminished Robot Research Club finally gets to show off its robot, and Akiho finally gets the chance to see her sister again.

Chaos erupts at the Robot Expo as Misaki starts destroying robots left and right. Meanwhile, slowly, but surely, Kaito begins to learn the truth behind everything.

With five billion lives at stake, Akiho declares that she WILL defeat Kou Kimijima! The question is... how?

Working through the night, the Robot Research Club members and the throngs of volunteers finish modifying GunBuild-1 before the Black Hole Bomb can be launched. The club members also devise a number of strategies for the upcoming final battle.

Kaito and Misaki face off in a final showdown with only minutes left until the BHB rocket is launched.

At long last, the Robot Research Club completes its giant GunBuild-1 robot! And, as people from all over the island watch, the robot takes its historic first step!

Akiho is elated when a grown-up Nae Tennoji offers to help the Robot Research Club build a giant robot. Meanwhile, Kaito is caught in a typhoon while searching for the elusive Kimijima Report No. 2.

The Robot Research Club's newest giant robot, GunBuild-2, is finally complete! Meanwhile, both Exoskeleton Co. and Mizuka catch wind of Kaito's activities surrounding Kou Kimijima.

Subaru and Kaito start practicing for the upcoming ROBO-ONE world tournament in Las Vegas. During his off-time, Kaito stumbles upon a mysterious room inside the abandoned folk museum.

Airi finds her existence threatened when major maintenance is scheduled for the IRUO. server. While Airi clings to the hope of a snowy miracle, Kaito learns more about her past.

Subaru seeks Kaito's help for the upcoming ROBO-ONE World Championship in Las Vegas. Meanwhile, Akiho struggles to keep the club funded while Kaito reflects on a life-changing incident.