A thirteen-year-old boy finds a man stabbed to death in a public air-raid shelter early in the morning. Detective Inspector Jago learns that he is Paul Ruckland, a school teacher with no known enemies and a pacifist--a member of the Peace Pledge Union. On searching his flat they're surprised to find a packed suitcase containing a revolver, a strange item for a pacifist to be carrying. Did he have enemies after all, or was he intent on harming someone--or even himself?
As the investigation gets under way, DI Jago discovers that Paul was not the only one whose pacifist convictions are challenged when the going gets tough. For many, anger and violence lie just below the surface. But who has a motive for murder?