The Devotion of Suspect X

One of the great mystery and thriller books of all time! (Time)
One of the best mysteries of the century! (Bookriot)

The Devotion of Suspect X tells the gripping story of Yasuko Hanaoka, a divorced, single mother who thought she had finally escaped her abusive ex-husband Togashi. When he shows up one day to extort money from her, threatening both her and her teenaged daughter Misato, the situation quickly escalates into violence, leaving Togashi dead on her apartment floor.

Overhearing the commotion, Yasuko's neighbour, middle-aged high school mathematics teacher Ishigami, offers his help. He not only disposes of the body but also meticulously plots the cover-up step-by-step.

When the body turns up and is identified, Detective Kusanagi takes on the case, and Yasuko comes under suspicion. Although Kusanagi cannot find any obvious flaws in Yasuko's alibi, he is convinced something is amiss. He enlists Dr. Manabu Yukawa, a physicist and college friend who often assists the police. Yukawa, also known as Professor Galileo, reconnects with Ishigami, a former college acquaintance. After their encounter, Yukawa becomes certain that Ishigami is involved in the murder.

What unfolds is a high-level battle of wits, as Ishigami attempts to protect Yasuko by outsmarting and outthinking Yukawa, who faces his most clever and determined adversary yet.