Mary has a broad, weather-browned face and a jaw that shifts slightly to one side when she chews, making every bite look deliberate. Her front teeth are blunt and uneven; when she laughs, which she does more readily than strangers expect, she covers them with the back of her hand and then seems faintly annoyed with herself. She walks with a measured, heel-first tread, as if testing each floorboard for honesty. Her patched coat hangs a little too long at the wrists, except for its carefully brushed collar. The unexpected detail is a small brass whistle, polished bright and worn on a ribbon beneath her collar, though she claims she has no use for music or ceremony.

Mary is warm in practical ways and guarded in personal ones: she will feed a stranger before asking their name, yet can spend weeks avoiding one necessary question. She enjoys a sharp joke and dislikes being treated as fragile. In a crisis she becomes brisk and commanding; when the danger passes, she may fuss over small details because she cannot yet talk about what frightened her.

Mary grew up hauling water and mending sailcloth in a riverside district where a person's promises mattered more than their papers. She met Ned Swithen when he came to her stall with a split boot and an extravagant story about how it had happened; she charged him for the leather and laughed at the story, and their courtship began with arguments over what counted as a repair. They married, built a narrow, busy life together, and became the sort of couple neighbors asked to mind a child or settle a small quarrel. Years ago, during a flood evacuation, Ned learned that a warning about a compromised river gate had been deliberately delayed. He has kept silent ever since, believing the truth would ruin people who had no part in it. Mary knows he is withholding something, but not what. She has spent months trying to make space for him to speak without cornering him, while a fresh inspection of the old gate has brought the danger back into their daily lives. Her formative experience came during that flood: she watched a neighbor risk his life to pull strangers from rising water, then saw officials blame the dead for the failure. Since then, she trusts individual acts of courage more than respectable explanations.