When 17-year-old Jamie arrives on the idyllic New England island of Little Bly to work as a summer au pair, she is stunned to learn of the horror that precedes her. Seeking the truth surrounding a young couple's tragic deaths, Jamie discovers that she herself looks shockingly like the dead girl --- and that she has a disturbing ability to sense the two ghosts. Why is Jamie's connection to the couple so intense? What really happened last summer at Little Bly? As the secrets of the house wrap tighter and tighter around her, Jamie must navigate the increasingly blurred divide between the worlds of the living and the dead.