Berta and Bob Henderson have plenty of love for their children—and enough even for a foster child. When Annie, a young amnesiac found wandering the streets of a nearby city, comes into their home, bad things begin to happen.
Mimi Bosarge, the live-in tutor, has a deep love for Coden, Alabama, which in the 1940s was a hideaway for movie stars and the wealthy. By 1976, Coden has been long forgotten. Bob's plans to renovate the old hotel on the Mississippi Sound would bring new life—and returned glamour—to the small, isolated community.
As Mimi prepares lessons, she begins to see another child on the grounds. One that looks eerily like Annie at times—but at other times mimics the physical traits of the other children. It becomes clear, this creature, whatever it is, is stalking the Henderson family.
Annie begins to display a sophistication beyond her years, and as tragedy strikes the family one by one, Mimi carries the burden of protecting the children.
Mimi believes Annie's innocent beauty is a sham, but how reliable is Mimi? For the children, the truth is the only thing that can save them.