The Siren Manifold

Every citizen of Harrowport knows the sound of survival: the deafening roar of the perimeter steam sirens, whose acoustic shockwaves shatter the occult horrors creeping from the salt marshes. Della Vinson doesn't hear the sirens—years on the high-pressure boiler gang took her hearing—she feels them in the iron decking beneath her boots. But when the horn manifold's pressure plunges during the highest fog-tide of the century, Della discovers saboteurs have slaughtered her crew and jammed the steam conduits. With the defensive sound wall failing and amphibious hulks tearing through the outer sea-gates, Della is the only technician left on the high catwalks. To save the lower harbor, she must superheat a fractured boiler and fire the sirens past their breaking point, even if the blast shatters her bones.