As a detective's personal life unravels, he must piece together the clues to a baffling series of murders in this Scottish Highlands crime thriller.

A family day out turns sour for DI McKay when he stumbles across an unidentified corpse. The day becomes darker still when his brother-in-law goes missing and is eventually found dead, the result of a seemingly accidental fall.

Meanwhile, DCI Helena Grant has a disastrous on-line date with a senior manager of a local hotel chain whose behavior escalates from pompous to downright disturbing. And, as she arrives home, she receives a threatening text from someone who has clearly been watching her. When a further body is found at the edge of the Cromarty Firth, McKay and Grant begin to piece together a grim tale of violence, human trafficking, and the darkest family secrets.