Hard luck story

Crane, a private investigator, is engaged by Josie Mellors to shadow her husband, whom she suspects of having an affair. But Mellors, Crane discovers, is loyal to his wife - just not to the letter of the law - and is being controlled by Docherty, a powerful gang leader. Docherty operates under such a convincing guise of total respectability that his affectionate family have no knowledge of his other life. When, by coincidence, details of his criminal activities emerge, the impact on his family is devastating and leads to a murderous climax.