The year is 2198, twenty years after the end of the artificial intelligence war.
Humanity has regained control of the cities, and intelligent androids have been almost entirely wiped out. Pure white skyscrapers cover the old battlefields. Citizens' ranks determine where they can live and what rights they have, old-fashioned machines are strictly regulated, and the last android rumored to possess independent consciousness is still hiding among the people.
University student Sakakibara Yu only wants a peaceful life, until his classmate Shiraishi Satsuki falls from a skyscraper and lands right in front of him.
A security system deliberately disabled for nine minutes, an old negative whose whereabouts are unknown, a group photo taken shortly after the war ended, and a stranger the victim insisted on identifying all lead the investigation to an android who disappeared twenty years ago.
Thanks to his past experience helping the police solve cases, Yu is allowed to join the task force. But as the investigation deepens, he begins to realize that the killer always seems to be one step ahead of the police. Altered dates, evidence claimed by impostors, and a warning hidden in an old recording also begin to bring a case from several years ago back into his life.
Someone is destroying the past. Someone else is protecting the secret in the photograph.
And Yu has yet to realize that as he tries to pick out the outsider from the crowd, a pair of eyes hidden in the darkness is watching him too.
