The Hog's Back is a ridge in Surrey and the setting for the disappearance of several locals. A doctor vanishes, followed by a nurse with whom he was acquainted, then a third person. Inspector French deduces murder, but there are no bodies. Eventually he is able to prove his theory and show that a fourth murder has been committed.
Dr James Earle and his wife live in comfortable seclusion near the Hog’s Back, a ridge in the North Downs in the beautiful Surrey countryside. When Dr Earle disappears from his cottage, Inspector French is called in to investigate. At first he suspects a simple domestic intrigue—and begins to uncover a web of romantic entanglements beneath the couple’s peaceful rural life.
The case soon takes a more complex turn. Other people vanish mysteriously, one of Dr Earle’s house guests among them. What is the explanation for the disappearances? If the missing people have been murdered, what can be the motive? This fiendishly complicated puzzle is one that only Inspector French can solve.