October 1987. A narrow iron bridge over Plum Creek, just outside the dead-end town of Bison Flats, South Dakota. Luna's cousin Harlan drove it every night for twenty-three years. Then one evening he saw a woman in a yellow dress standing in the middle of the span, her back to him, perfectly still. He slammed his brakes. She was gone. But the next night she was there again, closer. By the third night, she was pressing her palm against his driver's side window. Harlan never told anyone until he called Luna, two weeks before he died. Now Luna goes to see the bridge for herself. She finds a chipped iron railing, a rusted penny, and a name carved into the center beam — 'M. Callahan, 1891.' And then, just as she turns to leave, she hears a woman's voice, quiet and clear, asking her to stay.