In a quiet district of Tokyo, in broad daylight, a family of four is murdered in its own home. The killer flees, leaving behind a strange smell—something like the scent of incense—and a terrifying black sun drawn in soot on the ceiling. The detective who began the investigation throws himself into the river from the Rainbow Bridge. Inspector Kosuke Iwata and his slightly odd partner, Noriko Sakai, realize they’re facing a cold-blooded, calculating killer. They have every reason to believe he doesn’t intend to stop, and that the list of victims will soon grow. The next events will show that their intuition wasn’t wrong…