While consumer-use robots receiving the benefits of a networked society are becoming more widespread, the robot rebellion incident in February showed the vulnerability of that sort of information society. While it was a global crisis through the network, it was prevented by high school students of Tanegashima island, where the battle took place.
Half a year later. Tanegashima is flooded with people as it prepares for its summer festival. One of the high school students that saved the world from crisis, the protagonist Kaito Yashio, has since graduated and returns to his hometown of Tanegashima after a long time away.
During his return, he meets a middle-aged man named Itaru Hashida, who has a mutual friend and came to Tanegashima to see the sights. However, he cannot help but find his behavior strange. Although this man is actually a super hacker with world-class skills, Kaito has yet to learn this fact. Before long, events that disrupt everyday life start to repeatedly occur.
That was the sign of a conspiracy that is once again trying to throw the world into chaos.