On a beach not far from the isolated settlement of Sydney in 1797, a fishing boat picks up three shipwreck survivors, distressed and terribly injured. They have walked hundreds of miles across a landscape whose features - and inhabitants - they have no way of comprehending. They have lost fourteen companions along the way. Their accounts of the ordeal are evasive. It is Lieutenant Joshua Grayling's task to investigate the story. He comes to realise that those fourteen deaths were contrived by one calculating mind and, as the full horror of the men's journey emerges, he begins to wonder whether the ruthless killer poses a danger to his own family.