Falling Leaves is a murder mystery divided into two parts. The story begins in the autumn of 1983 in a small coastal town in Japan and describes the abduction of a thirteen-year-old girl on her way home from school. Mei Noguchi has been kidnapped – like many of her compatriots in the late seventies and early eighties – to teach Japanese language and customs to North Korean spies. Her parents spend decades in ignorance of the fate of their beloved daughter.
The second part of the story takes place forty years later. Mei Noguchi’s family has unsuccessfully campaigned for her release for over twenty years while, on another Japanese island, in another small town, the police are called on to investigate the death of Tomoko Gammo, a half-Japanese, half-Korean female university student at the local university found hanged in her dorm room. Interviews with Tomoko’s friends and professors reveal an atmosphere of whispered prejudice, academic pressure, and ideological conflict, with reports the student was bullied because her father was North Korean.
The local police at first suspect suicide, never dreaming that this death could possibly be connected to the fortieth anniversary of Mei Noguchi's disappearance. Chief Inspector Inoue and his trusted team of detective inspectors face their most challenging case yet in a race against time to apprehend the culprit before more lives are lost.