Northumberland, November 1809. A menacing figure stalks women through Hareshaw Woods and when Helen Carnaby, a beautiful young heiress, disappears from her locked bedchamber everyone fears the worst. The townsfolk cry 'witchcraft' and the local constabulary are baffled. Helen Carnaby's worried uncle sends for help from Bow Street magistrates' court in London. Detective Stephen Lavender and Constable Woods now face their toughest and most dangerous assignment. Convinced at first that this is just a simple case of a young woman eloping with a lover, Lavender and Woods are alarmed to discover a sinister, murderous world of madness, violence and secrets lurking behind the heavy oak door of the ancient pele tower at Linn Hagh. Why did Helen Carnaby flee on that wintry October night? How did she get out of her locked bed chamber? And where is she now? Hindered by Helen's uncooperative siblings, distracted by gypsies, rebellious farmers, highwaymen and an attractive and feisty Spanish senora, Helen Carnaby's disappearance is to prove one of the most perplexing mysteries of Lavender's career.