Milly has always had an extra persona inside herself named Amelia. Since the death of Milly's parents, Amelia has seemingly turned on her, becoming Milly's greatest adversary. Amelia constantly pours poison words into Milly's mind; she puts her down, coerces her into self-harm, and taunts her about committing suicide. When circumstances force Milly and Grandpa George, her current guardian, to move in with her estranged Aunt Rachel, Amelia pushes and pulls Milly along to discovering the two adults are hiding something. A fragile Milly re-discovers some of her own history that Amelia has blocked from her memory as well as learns some ultimately very disturbing family secrets.