Loch Aven is notorious in the small Scottish community of Blackhills. Twenty years ago, three young women disappeared, never to be found. The rumour to this day is that their bodies are still hidden in its dark waters. When Eleanor, Clio and Michaela find themselves rained out of a camping trip nearby, they have no option but to book mysterious Loch House on the banks of Loch Aven. Little do they know of its history, and that history is about to repeat itself... But when Michaela disappears, quickly followed by Clio, it becomes clear that something sinister is at play. As secrets in the tightknit community begin to surface, it's a race against time. Will the mystery of the Loch reveal itself before the dark waters claim their next victim...?