Youji, Kei, Kelly, and the bear-shaped robot Oscar save the town once more with the help of Fastening Machines! On this occasion, they encounter a kind-hearted young boy named Samhen and his AI robot, Jack. Samhen, who is shy and has transferred into Kei and Kelly's class, does not appear to enjoy talking about himself, but his talkative little companion Jack is more than willing to assist him in communicating. One peaceful afternoon, the young heroes must defend the town against sudden and serious danger! Will they manage to save everyone? Take note of the bond between AI and humans, which the children strive to protect!