Rules of Honour - The eighth Joe Hunter thriller

When Rink's father is brutally murdered, Joe has to stop his friend rushing headlong for vengeance. Because Rink's mother witnessed the crime and Yukiko isn't telling everything she knows. Her silence is governed by the Japanese tradition of giri, or moral obligation. But when there are more vicious deaths - all of them elderly men known to Yukiko - it becomes a matter of honour to uncover the shameful secret that lies behind the murders.
The killer isn't playing by the rules. But some rules are made to be broken and Joe doesn't care what he breaks to ensure Rink gets his revenge.