"Happy Valley" is a British multi-series dramatic detective story about police officer Catherine Cawood. She is a sergeant in the West Yorkshire Police. Catherine is on the trail of a criminal with whom she has a long-standing score to settle. One day, an accountant named Kevin comes to her police station and reports a crime. He is nervous and reluctant to share the details. It soon becomes clear that Kevin had once planned to kidnap his boss's daughter for ransom, but someone else has now carried out his plan.