Eleven years after the introduction of internet-connected, augmented reality eyeglasses and visors, YÅ«ko Okonogi moves with her family to Daikoku City, the technological center of the emerging half-virtual world. YÅ«ko joins her grandmother's "investigation agency" comprised of children equipped with virtual tools and powerful metatags. She quickly crosses paths with YÅ«ko Amasawa, an expert hacker of the virtual environment, as Amasawa relentlessly seeks to "unlock" the mystery of a computer virus that emerges from an inaccessible corrupted space.