Detective Inspector Montague Pluke, of CID, is England's most superstitious police officer. With crime at its lowest level for years, he decides to conduct a cold-case review. But there are no major unsolved crimes so, alerted by his wife, Millicent, to a large number of recent deaths – all attributed to natural causes – his expert knowledge of superstitions and folklore lead him to identify areas of suspicion sufficient to justify re-opening a case. Could an undetected mass-murderer be operating in Crickledale? His inquiries reveal that many of the deceased had been attended by Crickledale Voluntary Carers and he quickly produces a list of possible suspects. Indeed, the entire team of carers falls under suspicion – and Detective Inspector Pluke's wife, Millicent, is one of them.
