Living again of the Isle of Lewis, ex-Detective Inspector Fin McLeod is working as a security officer for a local landowner. While investigating illegal activity on the estate Fin encounters the elusive poacher and former childhood friend Whistler Macaskill. They witness a freak natural phenomenon-- a 'Bog Burst'-- which spontaneously drains a loch of its water, revealing a mud-encased light aircraft. Inside is the body of Roddy Mackenzie, a friend whose flight disappeared more than seventeen years before. Fin is unprepared for how the truth about the past will alter the course of the future.