They spread the maps out on a crate beneath the low tunnel lamp, faces bent close so the dim light would not give them away. The survivors had cleared a little alcove and dragged in a splintered table; on it lay a spread of ragged paper, faded ink, and the careful, trembling hand of a man who had seen the place change from workshop to slaughterhouse.
He called himself Merek. His hair was white as ash, and a long scar ran from his jaw to the corner of a mouth that still remembered smiles. When he spoke, his voice was gravel and memory.
"I helped build the lower works," he said, rubbing one knuckled hand across his brow as if trying to wipe away the images. "Not the heart—the maintenance rings, the conduits, the access tunnels. Back then it was a smithing complex. We forged tools, fixed pipes, kept the city gears from locking up. When the old city lord died, the new man didn't care for the smiths. They sold the place off to outsiders. Those outsiders had papers, silver, and robes. They said they would expand the city's light. Instead they bought machinery and stopped men from hammering. The forge became a lab. The hammers became cages."
He laid a finger on the map, index trembling. Ink lines traced tunnels, chambers, and a thick black circle where the engine lay. Around it were smaller circles and corridors: dormitories, storage vaults, purification vats, an upper intake, and, off to one side, a narrow maintenance shaft labeled in Merek's hand as the "black seam."
"If you can get in through the black seam," Merek said, "you bypass the first two rings of guards. It's narrow—too narrow for men in armor. I used it to snake new pipe runs when I wanted to work without the city hearing the hammer. It comes out behind the engine room's service wall." He paused. The map's ink shimmered faintly in the lamp's light. "From there, the access ladder takes you down to the subfloor where the soul conduits run. Cut them and the machine will choke."
Rena leaned forward, eyes sharp. "Where are the sentry posts? Where would the bandits place their traps?"
Merek tapped three small x-marks. "Main approach has the guard ring at the eastern courtyard. Anorus keeps men there—brutes with rune-banded axes. They protect shipments. Second ring's inside the maintenance corridor; that's where Sunoct keeps his watchers—mages that can sniff out mana. He also has three observation galleries on the mezzanine above the engine. From there they can lock the doors and seal the room."
Shadow traced the lines with a fingertip. The map fit like a cold truth beneath his skin. "If we slip the black seam," he murmured, "we avoid the courtyard. But once we're in the subfloor, we're trapped without an exit unless we create one."
Merek's eyes clouded, then sharpened. "There's an old refuse chute outside the eastern wall—used for slag. Too small for much, but if you widen the exit from below, you can bust out into the river bank. It buys you a minute or two—enough for a smoke and for anyone to drag kids out. The problem is the rigging. It's heavy, and the chute runs near the purification vats. One wrong move and the vats overflow."
Lena ran a hand through her hair, thinking fast. "What about Sunoct's position? Where will he be when they're running the morning batch?"
Merek hesitated. "He sits in the mezzanine most mornings. Watches through crystal lenses. Oversees the refinement phase. He likes to be where he can see the pods. Late shift—he moves to the control gallery. When the machine is stable, he's always near the observation posts to adjust the catalyst feed. If Anorus plans a shipment, he'll be with the guards by the courtyard. He trusts Anorus to handle collection. Sunoct trusts the machines."
Ryn's eyes flicked to Shadow. "Then we split. Quiet team goes through the black seam to the subfloor and kills the conduits. Loud team draws attention to the courtyard. Rena and Shadow take the subfloor—no showboating. Lena and I take flank, cripple the outer conduits. Sera keeps the children safe and handles anyone we can't kill."
Rena looked at Shadow. Her jaw set. "You ready to sink into the dark with me?"
He met her gaze and nodded. "We do it tonight. Low tide. The sewer's flow will help wash away any trace."
Merek swallowed hard. "If you go in, you'll see what we did. You'll see the little ones in the pods. You'll know the hands that fed them. I helped bolt the frames. I used to bring my son—he liked the hammers. They took him first."
He reached into his ragged coat and produced, with surprising care, an old brass key entwined with a sliver of blue cloth. "This opens the maintenance hatch at the black seam's entrance. I kept it because I thought… maybe I could come back and fix what was broken. I couldn't. I'm weak now. But you—if you go, make it quick. The engine won't cry for those it eats. It will simply keep humming."
Sera put a hand on his shoulder. "We'll bring them home."
Merek's face crumpled, relief and sorrow folded into one. "Then go with silence. Anorus's men listen for laughter. Sunoct listens for heartbeat."
They spent the afternoon marking the plan on fresh paper: entries, timings, signals. Shadow sketched the quickest route from the seam to the subfloor, drawing in not only passages but places to wedge a blade and a time to strike. Rena listed roles—who would cut the conduits, who would place charges, who would carry survivors. Lena and Ryn prepared small demolition kits from scavenged rods and wire. Sera made a row of small charms to block sedative fumes from the Veil; nothing permanent, but sufficient to keep a child breathing while they carried them out.
By dusk the map was folded and tucked into Shadow's cloak. He felt its weight like a promise. They ate a thin stew—the kind that tasted of metal and smoke—and packed what they could carry. Merek stood in the doorway for a long time, watching them ready themselves as if he could lend them a piece of his youth—an extra strike, one more hour of vigor.
"You're the kind who can get things done," he said softly to Shadow. "You were made for the dark places. Don't lose yourself in the machines."
Shadow did not answer, only checked the gauntlet one last time. The instrument hummed quietly beneath the skin of his arm—a steady, watchful thing that had become a nearly human companion.
Night fell thick and the city's pale lamps took over the sky. They moved out in a line—Rena and Shadow first, Lena and Ryn flanking, Sera and two of the stronger survivors in the rear with stretchers and packs. Merek stayed behind, hands pressed to his chest as some final prayer the smith once knew.
At the hatch, Shadow fitted the brass key. It turned with a tired, complaining noise and the seam opened onto a shaft that smelled of old coal and colder things. The black seam waited like a mouth. They slipped inside, one by one, swallowed by darkness and purpose.
Aboveground, in the square where the townspeople still looped their song, the world rolled forward untouched. Below, the plan had begun to sharpen into movement. The machines would not sleep forever. Neither would they.