Madeline Matheson, an expectant mother who has suffered numerous miscarriages, is determined to carry her pregnancy to term despite her doctor and loved ones' concerns. Tragedy strikes when a car accident leaves her unborn baby lifeless in her womb. Against medical advice, Madeline insists on delivering her stillborn child naturally. Miraculously, her daughter, Grace, is born alive, although something about her seems unsettling. Grace's survival brings both relief and alarm, as strange occurrences begin to arise, casting doubts on her normalcy.

As the days go on, Madeline becomes increasingly isolated, driven by a fierce maternal instinct to protect her daughter at all costs. Grace's peculiar condition and unexplained hunger lead Madeline down a disturbing path, forcing her to confront the horrifying reality of her child's nature. Conflicts intensify with those around her, especially her overbearing mother-in-law, forcing Madeline to make harrowing decisions. What begins as a story of miraculous birth transforms into a chilling exploration of maternal devotion and the lengths to which a mother will go to safeguard her child.