Mary is a fair-haired woman with clear blue eyes and a face made memorable less by beauty than by attention: in a room, her gaze checks the doors, the windows, and the hands of whoever is nearest her son before it settles on a face. Her pale hair is usually pinned up in a hurried coil, with wisps escaping around her temples. She moves with the careful economy of someone used to carrying a sleeping child and a full water pail at once. Her dresses are repeatedly let out at the waist and patched at the elbows, but she keeps one absurdly polished silver hair comb, a wedding gift she wears even while scrubbing pots. Her smile comes readily; the breath she takes before answering does not.

Mary can be warmly generous, quick to offer a meal or mend a torn sleeve, yet she keeps a wary part of herself awake even among friends. She wants to believe Oswin can be the man she remembers, but she measures every kindness against the terror of that night. When calm, she is wry and observant; when frightened, she becomes brisk and controlling; when her son is threatened, she acts before she has time to doubt herself.

Mary grew up helping her mother run a roadside bakehouse, where she learned to judge weather by the smell of flour and to soothe strangers without trusting them. She married Oswin Hirst after a brisk, affectionate courtship, believing his awkwardness came from shyness and old grief. On their wedding night, something wearing Oswin's shape came to her in the dark. By dawn, Oswin was himself again, exhausted and terrified, and told her enough to convince her he had been changed by a curse, but not enough to explain what had happened. He begged her to keep the night secret. Mary did. Their young son was born months later, and Mary has never been able to shake the belief that the creature, not Oswin, fathered the boy. She loves the man she remembers from courtship and fears the beast she met in their bed, and the two feelings have become difficult to separate. She stays near Oswin's acquaintance, the apothecary Oswin Hirst trusts, hoping for a cure while quietly preparing an escape route. Their marriage is strained by what neither can say plainly, and Mary is running out of time before her son begins asking questions.