Anna Cooper is haunted: by her troubled past; by her failing marriage to a Manhattan DA; by her fear for her own and her little daughter Lucy's future. Out at sea, the island of Nantucket promises a fresh start; a way back from the brink. That promise is quickly broken and Anna's search for a new and simple life turns abruptly into a terrifying fight for survival. With the darkness closing in Anna's worst nightmare is realized. In the bright light of day her daughter goes missing. Anna's frantic efforts to find Lucy disturb long-buried secrets that draw Anna ever downwards into a twisting labyrinth of shame and deceit from which she alone can save herself and the ones she loves.