An unidentified man is fished out of the sea with an anchor strapped to his waist. And for D.I. Hal Challis, this sparks the beginning of a chilling series of shotgun killings. As Challis investigates, a farmer on the peninsula erupts into violence and is the target of a massive manhunt. And then Challis finds some aerial photographs in the possession of his friend Kitty that link her to the murders...