A woman is found murdered in her new apartment in the Nihonbashi area of Tokyo. Living a quiet life, with nothing remarkable in her past and no known enemies, this newcomer's murder is as baffling as it was unlikely.

Detective Kyochiro Kaga of the Tokyo Police Department is also a newcomer to area--recently transferred to the Nihonbashi precinct. Assigned to the task force investigating the murder, Kaga interviews the various local people somehow connected to the victim--the insurance salesman whose card was found at her apartment; the local coffee shop she frequented; the boy who delivered a box of pastries; her estranged son, the would-be actor, among others. But the more Kaga pulls on the loose threads of a simple life, the greater the number of potential suspects emerge.

To prevent the murderer from eluding justice, Kaga must unravel all the secrets of the local residents, finding out the truth behind their interactions with the victim. Buried somewhere in the woman's seemingly uncomplicated life--her past, her friends, her family history, and the last few days of her life--is the one clue that will lead to the murderer.