In the 21st century, machines called Labors are widely used in the construction of a new Tokyo. A series of deadly accidents have befallen Labor operators at work on the Babylon Project--an initiative which seeks to redevelop Tokyo Bay. Following a mysterious plane crash over the bay, the young, headstrong detective Hata, and his mentor, the older, wiser detective Kusumi, are called in to investigate. It soon becomes clear to them that the plane crash was not caused by any outside threat, but by something that was on board the plane--something that is now loose in the bay. Their pursuit leads them into a web of lies, murder and multi-national conspiracy. Some secrets, however, don't want to be revealed, and the threat that lies just below the surface of the water threatens to emerge.