Long before Greta (Lauren Cohan) accepts her job as a nanny to that creepy doll, we learn that Brahms was, indeed, a real boy. He was a strange, quiet child who kept to himself. He would often play with the neighbor girl who was roughly his age.
One day, Brahms and his neighbor ventured into the woods, and while Brahms returned home safe, the young girl was never seen again. The rumors around town suggested Brahms had something to do with her disappearance.
On his eighth birthday, Brahms died in a tragic house fire. To cope with their loss, his parents replaced him with a porcelain doll and have cared for him as though he's real ever since.
Twenty years later, Greta accepts her job as a nanny to Brahms, the creepy porcelain doll we all know and love. Greta is on the run from her abusive ex-boyfriend, Cole, whom she has a restraining order against. She makes the acquaintance of a cute grocery delivery boy named Malcolm. Malcolm stops by once a week or so.
After going over all the rules, the parents leave, taking a "vacation."
Greta must follow a strict set of rules to please Brahms. This includes feeding him and storing leftovers in a huge freezer, playing music for him, kissing him goodnight, and more.
At first, Greta scoffs and shrugs off her responsibilities. But she soon comes to believe that Brahms is real. He can move himself. He seems to have an actual consciousness. As events progress, it appears that the porcelain Brahms is a sort of vessel for the departed soul of real Brahms.
In a disturbing sequence, the parents, who are on "vacation," write a mysterious letter and send it to the house. They fill their pockets with rocks and drown themselves.
Greta feels connected to Brahms and starts to see her caretaker duties as a way of mending her heart in the wake of her broken relationship.