The cast-iron access hatch of the plumbing wet-wall opened with a muted, oiled click.
Julian Vance stepped through the narrow opening first, his boots landing softly on the dusty wooden subfloor of the second-floor utility chase.
Behind him, Lin Mei climbed out of the vertical shaft, holding her brass flashlight shaded with her palm so only a pencil-thin beam pierced the darkness.
They were inside the service crawl space that ran behind the dormitory wall panels. Built in 1924, the narrow passage was barely three feet wide, wedged between the hollow plaster laths of the student rooms and the massive brick wet-wall.
To their left, the heavy waste pipes and cold-water risers vibrated with the deep, sixty-hertz hum of the building’s electrical ground. To their right, thin vertical gaps between the plaster laths offered narrow glimpses out into the second-floor corridor.
The corridor outside was pitch-black and empty, smelling of sulfur, scalded copper, and wet lime from the washroom bleed.
“The horsehair plaster absorbs ninety percent of the acoustic spill,” Lin Mei whispered, her lips inches from Julian’s ear. “As long as we keep our boots on the cross-joists, the floorboards won’t creak.”
Julian eased forward along the wooden joists, his shoulders brushing against the rough lath backing.
