Imagine you don't know your own darkest secret. But someone else does - and now they want you dead. Exhausted single mother Rebekah Murphy leaves her daughters with a friend in the city to accompany her brother on a work assignment on a picturesque island. An hour after arriving, her and her brother are attacked. He vanishes, she's left for dead and, by the time she makes it back to safety, it's already too late: the island has closed for the season - and it'll be seven months before anyone returns. But even with her brother missing, even with no boats, phones or people, Rebekah will soon realise that finding a way back to the mainland is only the start of her nightmare. Because someone is waiting for her - and they don't want her to make it home alive.