AI The scream hit Harlow Quinn before the smell did, a sharp echo knifing down the disused tunnel as she dropped from the train platform onto the gravelled track bed.
She straightened, brushed dust from her trouser leg and walked along the sleepers, ducking under the sagging strip of blue-and-white tape. Ahead, floodlights washed the abandoned platform beneath Camden in harsh white, turning every shadow into a deep black cut. SOCOs moved like pale insects. The scream came again, raw and wordless, from somewhere behind the lights.
Harlow did not look for its source. People screamed at scenes like this. Shock lived in the background. The body in the foreground told the truth.
It hung fifteen feet up, near the centre of the arched tunnel, suspended from an old steel cable that fed into the dark behind a rusted ventilation grate. The body spun slowly, toes an inch above eye level, suit torn, shirt blackened across the chest.
Harlow stopped under it, boots crunching ballast.
Behind her, footsteps slid down from the main platform. Loose gravel skittered.
"Quinn. Thought you hated the Underground."
"Thought you hated mornings," Harlow said.
DS Liam Patel stepped into her peripheral vision, tie crooked, beard two days past respectable.
"Crime scene pays better than sleep."
He tipped his chin at the body.
"Underground suicides are usually tidier."
"Suicides do not hang themselves from ceilings," Harlow said.
"Then we promote it to murder and still blame the trains."
She moved closer to the edge of the old platform, letting the lights catch every contour of the corpse. Male, late thirties, early forties. Thin. Office type. The face looked wrong, not slack like a hanged man, not purple with burst vessels. His skin sagged on the bone as if something had emptied him from inside out. Lips peeled back from teeth in a dry rictus.
His eyes had no pupils, only a uniform cloudy film, a bad cataract in fast-forward.
The burnt oval on his chest had a hard, distinct edge. No spray. No fissures. No charring around it.
A perfect circle of impossibility, about the size of a dinner plate.
"ID?" she said.
Patel pointed with his pen.
"Wallet in the jacket. Name's Daniel Mercer. Corporate badge says he worked two stops away. Bank type."
"When did he clock off?"
"Apparently never came in. Wife reported him missing last night when he skipped dinner and password-locked his phone. Uniforms did the welfare check. Empty flat."
Harlow watched the slow spin of the body.
"Who found him?"
"Track inspector. Contracted engineering team. Came down to document subsidence in this abandoned section. Saw old mate here dangling where no one should dangle. Threw up, called it in."
The scream cut the air again, closer this time. Harlow glanced sideways. A young PC near the coping stones had his back pressed to the old tiled wall, hand over his mouth. He retched into it, body folding.
"First floater?" Patel said.
"First hanger."
Harlow let him deal with the constable. She stared past the body, at the way the cable disappeared into the dark behind that grate. The metal had an old London Underground red-brown rust but the point where the cable met the frame looked clean. No corrosion. A bright, scored groove like a fresh cut.
Something had pulled weight against that edge recently. Hard.
She paced along the length of the platform, tracking the path of the cable with her eyes. It angled up along the tunnel crown, tied into an old bracket, then vanished into the side arch on the far end, where an iron door, half off its hinges, gaped into darkness.
Closed station, old rumours, urban explorer videos that Internal sometimes passed around on bored afternoons. This had been one of those ghost platforms you saw flash past between stops if you squinted.
Harlow had never liked rumours.
She had seen what lay beneath them.
"Where were the track inspectors working?" she said.
"Over there. Left of the arch." Patel checked his notebook. "They were supposed to survey subsidence in the service tunnel."
"Get the SOCO to photograph the feet before they cut him down," she said.
"Feet?"
"Always look at the shoes."
He lifted an eyebrow .
"You going to start quoting your old training sergeant again?"
"He died," she said, too flat . "So no."
He had the sense to shut up.
Harlow crouched at the edge of the ballast and scanned the floor beneath the body. A thin ring of brown dust traced a circle, faint but even. Not the random scatter of filth, something laid down with intent. In the beam of her torch it looked almost granular, fragments of something ground and mixed.
In the circle, the gravel bed lay oddly clean. Beyond it, dust thickened on the sleepers and on the curled cable sheathing along the wall. No footprints in the ring, no drag marks, no scuff of post-mortem staging.
The body hung dead-centre.
"See this?" she said.
Patel stood beside her, peered down.
"Someone needs to get better at sweeping."
"The opposite," she said. "Someone kept that area clean."
He shrugged.
"Okay. Cult stuff. They love a circle. Lucky we did not find goat heads."
Harlow's jaw tightened.
"Cult stuff is messy. Wax, ash, cheap knives. Photos of their work on Instagram. This is precise."
"Are you complimenting the killer's housekeeping?"
She ignored him, focused on the dust itself. She slid a latex glove on, pinched a little between finger and thumb. The grains did not feel like soil from the tunnel, no damp grit, no smell of oil. Dry. Brittle. It crunched like bone.
Copper pricked her nose. Not heavy, faint. Old blood, but not from the circle.
She straightened, turned the torch on the corpse's hands. The fingers curled stiffly, nails cracked. The inner palms, what she could see through the twist, showed dark smears, as if he had gripped something that left residue.
"Photos from before anyone touched him," she said.
"On the server already," Patel said. "SOCO officer nearly walked right through your precious circle."
"Do you see drag marks?"
He scanned the ballast, the track, the gaps between sleepers.
"Maybe they lifted him straight up with the cable. No need to drag."
"With what? A cherry picker?"
He flashed her a quick grin.
"Urban explorers. Tripods. Ropes. They come down here at night, they see all this, they think, what a lovely creepy spot for some performance art. Goes wrong."
"Urban explorers tidy less than cultists," she said. "And they film everything."
"Then this will hit YouTube in a week and validate your cynicism."
She walked away from him, along the platform, as a SOCO shouted that they were ready to bring the body down. The old tiles lining the walls had once been white but decades of smoke and grime had turned them a mottled nicotine beige. Spray paint sprawled across some, dense, overlapping tags and sigils. Not the occult kind, the teenage territory kind. Except for one patch where the graffiti stopped.
In that clean space, about shoulder height, someone had scraped away the soot and dirt in a careful circle. Pale tile gleamed underneath, fresh exposed. Around its edge, four small lines radiated like compass points, etched deep into the ceramic. North, south, east, west.
In the centre, scratched so fine you needed the correct angle to catch it, lay a tiny spiral, no bigger than a coin.
Her neck prickled.
"Get me close-ups of this," she called over her shoulder.
"What am I shooting?" a SOCO said.
"Scratches."
"Those? Could be anyone with a key."
"Keys do not carve spirals that neat," she said. "You would slip."
Behind her, the winch creaked. The body jerked as they began to lower it. A chorus of camera shutters crackled, crisp and insect-like.
Harlow kept walking, drawn toward the iron door half off its hinges at the end of the platform. Rust flakes crusted its edges, the padlock long since cut. Beyond it, her torch beam caught the start of a passage, brick arch close and low, cable runs snaking along the ceiling.
As she stepped through the doorway, the air changed. Colder, still, a different kind of old. Not the damp of unused tunnels, something drier. Preserved.
"Quinn." Patel 's voice echoed back from the platform. "Stay in sight, yeah? I am not fishing you out of some Victorian well."
"Then do not lose line of sight," she said.
She followed the curve of the corridor for several metres, her light lancing ahead. On the left, a series of bricked-up arches. On the right, one metal gate, bars bent back at the bottom just enough for a slim person to squeeze under.
Someone had used that gap recently. Dust streaked, not settled. No cobwebs across the warped space.
She crouched, shone the torch through.
Beyond the gate, the tunnel opened into a wider chamber. Her light skimmed over shapes that did not belong to the Underground: tables, collapsed and stacked; crates shoved against walls; a row of makeshift stalls made from scaffolding poles and planks. Scraps of coloured fabric fluttered in the stir her breath pushed through the bars. A paper lantern, long dead, dangled on a frayed cord.
This had been a market once. Not for tourists.
Her chest tightened, a memory trying to claw its way up. Morris, three years ago, chalk dust on his fingers, eyes too bright, talking about a place under the city where the rules bent. A joke at first. Then less of one.
She dragged her mind back to the present.
Something glinted on the floor just inside the gate. Small, round, brass. It had rolled against one of the bars and lodged there, trapped.
Harlow reached under, glove squeaking on metal, and fished it out.
A compass sat in her palm. Old, small, the brass casing stained with a greenish patina of age. The glass over the face had a hairline crack. Etched into the metal around the edge, not Latin, not Greek, but something that made her eyes not quite want to focus . Sigils. Protective or predatory, she could not tell at a glance.
The needle did not point north. It quivered , steadying in the direction of the tunnel behind her, back toward the main platform. When she turned it, the needle resisted, swung back, aligned itself like a stubborn animal scenting home.
"Find a souvenir?" Patel 's voice came closer.
She slipped the compass into her coat pocket before he rounded the bend.
"Just rubbish," she said.
He peered through the gate.
"Bloody hell. What did they sell down here, asbestos and rat poison?"
"Pack it as a possible secondary scene," she said. "We get a warrant, we search it properly. No one squeezes under those bars without my say."
"You think our banker did his last shop down here?"
"I think our banker met someone he should not have," she said.
"Mercer has no record," Patel said. "Not so much as a parking ticket. Wife says he works twelve-hour days, gym twice a week, drinks only at Christmas. No skeletons."
"Everyone has skeletons," she said. "Some people hide them under Camden."
He snorted.
"You heard the track guy's story yet?"
"Enlighten me."
Patel leant one shoulder against the cracked brick, careful of his suit.
"Bloke swears the place looked different when he came down. Says there were lights past this arch. Voices. Music even. Then his torch died. He bangs it, it comes back up, and poof, disco gone, dead man here. Says he will never touch a train again."
"Alcohol?" she said.
"On shift? He seemed straight. Shaken, but that is expected. He kept insisting it smelt like incense."
The faint trace in the air tickled her now that he said it. Not strong, not recent, but threaded through the cold bricks: resin, smoke , and something sharper underneath, like sliced citrus left to dry. Clinging in a space the public had not accessed for decades.
"Lights and voices in a closed tunnel," she said. "How many exits?"
"Officially? None. That gate. The hatch the inspectors used. And the main access up to the public platform. We checked. All locked except the hatch."
"You always believe your own locks?" she said.
He hesitated.
"What are you thinking? Magic market? Ghost rave?"
She started back toward the main scene.
"I am thinking we have a body that does not fit the environment. Witness testimony that does not fit the layout. And dust patterns that do not fit the staff."
"Or we have a stressed contractor seeing lights and our killer using a handy abandoned station with dramatic flair."
"Dramatic flair does not sand its own footprints," she said.
On the platform, the body lay on a yellow tarp, limbs at awkward angles, SOCOs buzzing around it. Someone had peeled the shirt back. The circular mark on the chest looked worse up close. The skin had darkened to a deep, even black, like it had been cooked under a clean, merciless heat. No blistering. No gradation. A neat disc of ruin.
Harlow stepped in, ignoring the look from the crime scene manager.
"Anything under the shirt pocket?" she said.
"Only this," the SOCO said. "Left trouser pocket too."
He gestured at a small evidence tray already labelled. Inside sat a phone sealed in a bag, a silver money clip with notes, keys on a leather fob, and a thin disc of bone roughly the size of a fifty-pence piece. Someone had bored a hole through one edge and threaded a black cord through it.
Even under the fluorescent glare, the bone looked old. Polished by many fingers. Faint carvings ringed its surface, worn almost smooth, a suggestion of tiny triangles and hooked lines.
Her stomach dropped.
Morris had showed her something like that once, on a long stakeout , rolling it between thumb and forefinger like a gambler's chip. Said he got it from a bloke who knew a bloke, entry token to a place beneath the city where you could buy anything if you knew how to look.
He had gone into a condemned warehouse two nights later and never walked out.
Harlow looked up sharply .
"Where did you find the bone disc?" she said.
"Right pocket," the SOCO said. "Against his thigh. No chain, just loose. Why?"
"Because it does not fit a banker," Patel said. "Unless he moonlighted as a shaman."
Harlow forced air slowly out of her lungs.
"Get close-ups. Both sides. Check it for prints and DNA. Bag it separate, mark it priority."
"You want me to phone the occult unit while I am at it?" Patel said.
"They will phone us when it leaks to the press that we found runes on a corpse," she said. "Better to stay ahead."
"Says the woman who thinks cultists are messy."
"Everyone is messy," she said. "Patterns are the only clean thing."
As the SOCO bent to take more photos, the overhead lights flickered . Once, a stutter that washed the tunnel in grey, then stabilised. Conversations paused, then resumed with that forced casualness people used when they ignored something that unsettled them.
In Harlow's pocket, the weight of the little compass shifted as if someone had nudged it. She slipped a hand inside, closed her fingers around it.
The metal felt warmer than it should in the chill air. The needle jittered under the glass. When she tilted it a fraction, it did not fight like before, it swung fast, pinning itself toward the far end of the platform, to the gate and the secret market room beyond.
A hush passed through the tunnel, so slight she almost wrote it off as her imagination. Sound thinned. The hum of the generators dipped, the rustle of paper bags and the soft murmur of voices dropped half a note.
Then the brick wall behind the bent gate exhaled.
Not air, not exactly. A pressure change brushed her skin, made the tiny hairs on her arms stand to attention. Dust sifted from a crack that had not been there five minutes ago. It traced a jagged vertical line up the mortar, right where her hand had scraped under the bars.
The compass needle slammed against the glass, fixed.
"Quinn," Patel said quietly at her shoulder, following her stare. "Tell me you see that."
The crack widened in silence , bricks grinding like low thunder, and a thin, black line opened in the wall, darker than the dark around it, as something on the other side pressed to get through.