Guilt. by the million - copy bestselling author of The Devotion of Suspect X

A tour de force crime novel from one of the international masters of the form, where a simple murder case questions the simple notions of good and evil, guilt and redemption. A body has been found on a Central Tokyo riverbank, and Homicide Detective Godai of the Tokyo Metropolitan Police Department is assigned to investigate. The victim is identified as a lawyer, Kensuke Shiraishi, and Godai's investigations lead him to one Tatsuro Kuraki, who ends up confessing to not only to the lawyer's murder, but also another one from thirty years ago - for which another man was arrested and died in custody before trial.
Kuraki's confession neatly resolves two cases, but there is just one problem: Detective Godai doesn't believe him. What's more, there are two other people who can't accept Kuraki's confession. One is the son of Kuraki, the professed murderer; the other is the daughter of Shiraishi, the victim. As they get closer to the truth it becomes clear that the link between the two murders is murkier and more complicated than they could possibly have imagined - and so is the line between innocence and guilt.