Review of The Devotion of Suspect X by Keigo Higashino (2012, Abacus; 2005, Japanese)

Yasuko Hanaoka is a divorced, single mother. A former nightclub hostess she now works in a local takeaway where her neighbour, a high school mathematics teacher, Ishigami buys his lunch each day. One day her former husband, Togashi, turns up looking for money and threatening continued harassment. The confrontation spirals out of control, ending with mother and daughter killing Togashi. Hearing the commotion, Ishigami offers to help get rid of the body and to plot the cover-up. All Yasuko and her daughter need to do is stick to the story Ishigami creates for them when questioned by the police. Detective Kusanagi can find no holes in Yasoko’s alibi, but there is something about the case that un-nerves him and he turns to his friend, Manabu Yukawa, a university physicist, for help. Yukawa was a friend of Ishigami at university and knows him as a mathematics genius. He’s somewhat surprised that Ishigami is a high school teacher, but knows that if he is involved in the case that it will be fiendishly difficult to solve.

Set in Tokyo, The Devotion of Suspect X is a police procedural with a difference. The reader is presented with the murder at the start of the novel. Yasuko Hanaoka and her daughter murder her abusive former husband. Their neighbour, Ishigami, who is smitten with Yusuko, hears the fight and offers to help them dispose of the body and create a cover-up. A body is subsequently found, quickly identified and the police turn up at Yashuko’s door. It appears though that she has a verifiable alibi for the time of the murder and she’s sticking to pleading ignorance. The unfolding story then revolves around the police probing the alibi and trying to trace Togashi’s last movements, with the mystery essentially being whether they’ll be able to get to the truth given Ishigami’s carefully plotted cover-up. There are two unaccounted element in Ishigami’s machinations. The first is Yashuko, who takes up with an old flame in the days following the murder. The second is Ishigami’s former university friend, Manabu Yukawa, a physicist who occasionally helps the police. Yukawa knows that Ishigami is a genius. What ensues is a battle of wits based around a mathematical philosophical question: what is harder – devising an unsolvable problem or solving that problem and knowing if it is correct? A cat and mouse game evolves, with Ishigami tweaking his plan in light of unfolding events. The police, however, remain baffled. The story and characters make for interesting reading, though the tale slows to a crawl at times with only the hook of wanting to know if they’ll be caught keeping the pages turning. The patient build-up is, however, worth it. Despite having sight of all sides in the game, the pay-off for the reader is the double-twist in the denouement, the first of which is somewhat unexpected and breath-taking, despite the fact that the book is marketed heavily on its existence. It’s relatively rare to come across a twist so clever that is not a blindsiding but makes perfect sense in relation to the rest of the plot. And the ending is just perfect. Overall, an absorbing, clever tale of clever scheming; a mostly four star read elevated by a philosophical spin and a very well executed denouement.