On the Nihonbashi Bridge in Tokyo stands the statue of a mythic beast – a kirin. One evening a man staggers onto the bridge and collapses beneath the winged creature. The patrolman on watch goes to rouse the man, who he presumes to be drunk – only to discover that the man had been stabbed in the chest. He is dead.

Meanwhile, a young man named Yashima is injured in a car accident nearby while trying to flee from the police. Found on him is the wallet of the murdered man.

But is he actually responsible for the crime? What is his connection to the victim? And why did the dying man drag himself from the crime scene to the Nihonbashi Bridge? Tokyo Police Detective Kyoichiro Kaga must piece together the answers to all of these questions in order to find the killer, but each answer he finds seems to throw up more questions …