Dai Morgan has the body of a man and the mind of a child. He lived with his mother in the Mid Wales village of Llan, next door to bright, beautiful 19 year old Anna Harris. The vicar found Anna's naked, battered body in the churchyard one morning. The police discovered Anna's bloodstained earring in Dai's pocket. The judge gave Dai life. After ten years in gaol Dai appealed against his sentence and was freed. Sergeants Trevor Joseph and Peter Collins are sent to Llan to reopen the case. But the villagers refuse to believe Dai innocent. The Llan police do not make mistakes or allow murderers to walk free. Do they?