1956. When a young man is kidnapped, then turns up, unharmed the next day, the affair is dismissed as a joke. When another person goes missing, the CID takes an interest, and Constable Deepbriar finds himself at the heart of a murder investigation. When a friend disappears, he has to risk his own life to prevent the murderer from claiming yet another victim.
As Minecliff prepares for its summer fête, Constable "Thorny" Deepbriar is called to an unpleasant incident involving an illegal mantrap. With a madman causing mayhem on the local byways, and a malicious writer of anonymous letters, the constable faces a serious challenge to his detective abilities, and ultimately a threat to his life.