A remote deserted island off the coast of Maine holds dark memories and disturbing secrets for the family who once lived on its rocky shores. Though nineteen-year-old Sally de Gama remembers nothing about the accident that took place on Captain's Island and destroyed her family when she was a little girl, she suffers from intense anxiety, pervasive bouts of dissociation, and gruesome nightmares. All Sally knows is that her mother hasn't spoken since the accident that took the life of Sally's twin sister. Following the tragedy, her family fled and never looked back. When her mother suddenly dies, Sally and three college friends travel to the island - for her friends it's an adventure to a strange, abandoned place. For Sally, it's a desperate bid to recover some of her memories and understand what really happened to her family. But when memories begin to return, Sally is overcome by grief and rage that threaten to plunge her into madness - a madness that is fed by a malevolent presence stalking them on the island.