Lauren Cohan stars as Greta, an American woman who takes a job as a nanny in England in order to get away from a dangerously abusive and obsessed ex.  It's a large and isolated country mansion owned by an older couple called the Heelshires, who expect Greta to cater to the every needs of their eight-year-old boy, Brahms, as they go away on holiday.  Greta finds out the reason why they've had difficulty keeping prior nannies on hire once she meets Brahms, as he turns out to be a doll, literally, life-sized, and made mostly of porcelain.  The Heelshires maintain that their boy, who died in a house fire two decades prior, is very much alive in this doll, and he has particular needs that Greta must fulfill to keep him happy, one of them being that the only person other then the Heelshires allowed to come over is the delivery man, Malcolm.  Greta initially think the notion is absurd, but a job's a job, but soon discovers there may be some truth in the assertion that Brahms is very much alive, and isn't going to take kindly to her not following his rules, or attempting to leave him there alone.