Millicent Pluke, the devoted wife of Detective Inspector Montague Pluke, stumbles across a woman's body by Devil's Dump, a pool in a remote North Yorkshire moorland stream. Her discovery means Pluke must steel himself not to hunt forgotten horse troughs - the passion of his life - but instead to track down a murderer. As his enquiries intensify, Pluke suspects the ruined Trough House may provide important clues but when he discovers the body has previously been buried but flushed from its well-hidden grave by the ferocious St Margaret's Day flood, his knowledge of moorland folklore becomes vital to the investigation. A maiden's garland was discovered with the body, but why would a murderer take the time and trouble to bury the garland - a symbol of purity - with the victim? Pluke's research unearths that others have also died in Devil's Dump - in 1821 a shepherd name Featherstone drowned in its depths and again, in 1872 another tragedy occurred in the waters; another Featherstone, but this time the victim was a six year old girl who was later buried with a maiden's garland. And now Susan Featherstone has gone missing from the dale - and she is an agent for an artist who always depicts a shepherd in her paintings of the moors. But the artist too has gone missing, so is Susan victim - or killer?