Fauldmere is a nature reserve on a lonely peninsula, and Doctor Frost and his wife planned a quiet summer holiday there. But it wasn't to be. For no sooner had they arrived than they heard of the strange disappearance of a local youth and his girl. Were they still on the reserve? And, if so, were they dead or alive? Doctor Frost investigates and uncovers clues which indicate premeditated murder, the outcome of a web of crime. But the key to the puzzle lies somewhere in the reserve itself, between the grim stone quarries and the bleak shores of the creek.