Following a term-end school ceremony, Bobby and his friend Akkun venture into the mountains outside their village, to a location ideal for a covert base. They make a pit stop along the route at a weird amusement park. They had a good time there, but are attacked and are unable to escape. They join forces with a group of other children who are also stuck there, and together they fend off a series of attacks, gradually learning the truth about the institution.