AI Detective Harlow Quinn found the entrance between a shuttered tattoo parlour and a kebab shop that had failed its hygiene inspection twice.
At first glance, there was nothing to distinguish it from the other service doors along the Camden side street. Flaking black paint. A rusted mortice lock. Three dead flies trapped in an outdoor light. But someone had looped blue-and-white police tape through the handle, and a constable stood beneath the awning with rain dripping from the peak of his cap.
“Detective Quinn.”
She showed her warrant card anyway. Eighteen years had taught her that procedure mattered most when everyone else had decided it didn’t.
The constable lifted the tape. “Scene’s downstairs. DI says mind the third step.”
“Why?”
“It bites.”
Quinn looked at him.
“That’s what Forensics said.”
His face remained earnest, which made it worse.
She ducked under the tape and opened the door. Damp air breathed up from the stairwell, carrying old iron, wet plaster, and a sweeter smell she couldn’t place. Not rot. Not quite incense. The stairs descended steeply beneath a green emergency light.
The third step bore a chalk circle and a yellow evidence marker. Its edge had splintered inward as if struck by a tool. Quinn stepped over it.
At the foot of the stairs, the passage opened onto an abandoned Tube platform.
White tiles curved along the walls, most browned with age. Fragments of an old station name survived beneath soot and layers of torn posters, but someone had painted over the letters with black tar. The rails were gone . The track bed had been boarded across with mismatched planks, turning the whole place into a broad, subterranean hall.
Stalls crowded both platforms.
Some were skeletal frames draped in black cloth. Others had been built from cabinets, wardrobes, railway luggage carts, and what looked like the prow of a narrowboat . Copper pipes ran overhead, hung with charms that clicked in the draft: teeth, keys, glass eyes, tiny cages. Hand-painted signs advertised impossible wares.
MEMORIES — CLEANED, COPIED, RETURNED.
WOLF SALT. NO REFUNDS.
NAMES BOUGHT BY WEIGHT.
The crime scene officers had stopped at the edge of the concourse. Beyond their portable lamps, the Market vanished into a murk of folded awnings and narrow aisles.
Sergeant Bell waited beside a tea stall with both hands thrust into his coat pockets. He was broad, tired, and twenty years too old to be impressed by anything. At present, however, he was staring at a row of stoppered bottles in which pale lights pulsed like slow heartbeats.
“Don’t touch those,” Quinn said.
“I wasn’t going to.”
“You were leaning.”
“I can lean without touching.”
“That belief has cost the Met money before.”
Bell turned. Relief softened his face. “Quinn. Glad you’re here.”
“Constable upstairs says the steps bite.”
“They got Patel .”
“Bit him?”
“Bootlace tied itself to the bannister. He nearly broke his nose.”
Quinn glanced back toward the stairwell.
Bell added, “That isn’t the unusual bit.”
“Good.”
He led her past a stall stacked with tarnished mirrors. Each had been covered with muslin, though one cloth had slipped, exposing a thumb’s width of glass. Quinn saw darkness reflected there, empty and deep. No lamps. No platform. No Quinn.
She kept walking.
“The place calls itself the Veil Market,” Bell said. “Hidden market, occult goods, contraband. Vice had rumours. Never found an entrance.”
“Who did?”
“Uniforms responding to an anonymous call at three seventeen. The door was open. Caller said there’d been a murder under Camden, then hung up.”
“Trace?”
“Burner. Signal bounced off six towers in under a minute.”
They turned into a narrow aisle. Shelves pressed in on both sides, crowded with packets of grey powder and bird skulls fitted with silver beaks. The sweet smell strengthened.
“Where are the traders?” Quinn asked.
“Gone. Whole place abandoned when uniforms arrived.”
“How many exits?”
“One found so far.”
“A market this size doesn’t survive on a single staircase.”
“My thought exactly.”
“No, your thought was that the glowing bottles were pretty.”
“They are pretty.”
He stopped before a stall enclosed by green velvet curtains. A crime scene photographer crouched at its entrance. Two lamps threw hard white light across the interior.
A man lay behind a walnut counter.
He appeared to be in his fifties, though the puckered skin around his eyes made age difficult to judge. His hair was silver, long enough to brush his collar. He wore a plum-coloured waistcoat over a white shirt. No shoes. His feet were clean.
One hand rested on his chest. The other dangled toward the floor. A knife protruded beneath his ribs.
Blood had soaked his waistcoat and spread in a dark fan across the boards.
Quinn stopped outside the curtain.
“What do we know?”
“No identification,” Bell said. “No wallet, no phone. Stall inventory suggests he sold navigation tools.”
The shelves behind the corpse held astrolabes, lodestones, sextants, pendulums, and compasses in dozens of shapes. Some were ordinary brass instruments. Others had faces marked with alphabets Quinn didn’t know. One glass dome contained a black needle that spun continuously without slowing.
“Time of death?”
“Pathologist’s estimate is midnight to two.”
“Temperature down here?”
“Fourteen degrees when we arrived.”
“Any environmental anomalies?”
Bell rubbed his chin. “That’s becoming a normal question far too quickly .”
“Answer it.”
“Cold patch by the back wall. Seven degrees. Infrared won’t read the victim’s left hand properly. And every compass in the stall points at the body.”
Quinn looked.
He was right. Needles on shelves, beneath glass, hanging from strings—all leaned toward the dead man. Not north. Toward him.
The photographer’s camera clicked. The needles twitched in unison.
“What’s your different interpretation?” Quinn asked.
Bell frowned. “Different from what?”
“You only get that careful when you’re about to tell me my crime scene isn’t a crime scene.”
He sighed. “Doctor thinks suicide staged to look like murder.”
“With a knife under the left ribs?”
“Blade angle suggests self-infliction. No defence wounds. No signs of struggle. Curtains closed, valuables untouched. Blood on his right hand matches the wound. He grips the knife, drives it in, lies down, puts his hand on his chest.”
“And then removes his shoes?”
Bell glanced at the bare feet. “Could’ve been some sort of ritual.”
“Everything becomes a ritual when no one can explain it.”
“At an underground magic market?”
“Especially here.”
She put on gloves and entered the stall.
The sweet smell was sharp inside, almost medicinal. She crouched beside the body without touching it. The knife had a bone handle carved with a spiral. Its blade entered at an upward angle. There was blood on the man’s right palm and between his fingers, but none along the bone grip visible above his waistcoat.
Quinn leaned closer.
“Photograph the handle,” she said.
The photographer shifted position.
“Already did.”
“Do it again.”
The flash whitened the stall.
There was a narrow smear on the counter’s edge, reddish brown and half dried. Quinn followed its direction. It began near the corpse’s dangling hand and ran toward an empty patch on the countertop.
Dust outlined a small circular object that was no longer there.
“How thorough was inventory?”
“Still ongoing,” Bell said. “There are several hundred objects.”
“This was removed recently.”
He crouched beside her. “Round base. About six centimetres.”
“Not a base. A compass.”
She looked across the cluttered shelves. Most instruments wore a film of dust. A few had been handled , leaving crescents and clean arcs, but the circular absence on the counter had a faint green stain around its rim.
Verdigris.
The blood smear passed directly through it.
Quinn studied the body again. No blood on the knife handle. Blood on the palm. If he had stabbed himself, his hand would have transferred blood to the grip only after the wound began bleeding, unless he had released it at once. Yet the placement was too tidy, the hand arranged across the chest like a portrait of death.
“What did he touch?” she asked.
“The knife, presumably.”
“No. Someone put his blood on his hand to suggest that. But they missed the handle.”
Bell’s expression sharpened. “So murder.”
“Possibly.”
“You hate giving me the whole word.”
“It encourages you.”
Quinn lowered her gaze to the floor. Blood had run between the boards, but the pool’s shape bothered her. The thickest concentration lay beneath the dead man’s shoulder, not below the wound. A dark ridge marked where liquid had met an obstruction that was no longer there.
She pictured the body elsewhere. Moved after bleeding. But there were no drag marks, no bloody footprints.
His clean feet.
“Where are his shoes?” she asked.
“Haven’t found them.”
“Because he didn’t walk here.”
Bell nodded slowly . “Carried?”
“Then someone carried a bleeding man through the Market without leaving a trail.”
“Could’ve wrapped him.”
“The blood pool says he bled here.”
She reached toward the victim’s shirt cuff, then paused. A single curl of red hair clung to the white linen. Bright under the lamp. She pointed it out to the photographer and waited while it was bagged .
“Female suspect?” Bell asked.
“Or male. Or neither. Hair is evidence, not a biography.”
A noise came from the aisle.
One of the constables said, “You can’t go in there, miss.”
“I know what that is. I work with artefacts. Well, adjacent to artefacts. Technically below artefacts, in an archival hierarchy that’s frankly medieval—”
A young woman appeared between the curtains, shepherded by a constable who looked as if he regretted every decision that had brought him underground.
She was small, freckled, and drenched from the rain. Curly red hair framed round glasses fogged at the edges. A worn leather satchel bulged with books at her hip. She saw the body and stopped so abruptly that the constable bumped into her.
“Oh,” she whispered.
Her left hand rose. She tucked a curl behind her ear.
Quinn looked at the evidence bag in the photographer’s hand.
Then at the woman’s hair.
Bell muttered, “Well. That’s convenient.”
Quinn stood. “Name.”
“Eva Kowalski.”
“Reason for entering a sealed crime scene.”
“I didn’t enter the crime scene. I entered the Market. Your officer directed me here after I showed him this.”
Eva held out a small object. It was carved from bone, oval and yellowed, with a hole bored through the centre.
Quinn didn’t take it.
“What is it?”
“An entry token.”
“For the Veil Market?”
“Yes.”
“Where did you get it?”
Eva’s fingers closed around the token. “From a contact.”
“Name.”
“I can’t say.”
“You can.”
“I mean I won’t.”
Military habits returned to Quinn in moments like these, old as muscle: assess posture, hands, exits, threat. Eva’s breathing was shallow. Her eyes kept flicking toward the corpse, but not with shock alone. Recognition sat there.
“You knew him,” Quinn said.
Eva tucked her hair behind her left ear again. “I knew of him.”
“Who is he?”
“They called him Sable.”
“Real name?”
“I don’t know.”
“What did he sell?”
“Ways through.”
Bell gestured at the shelves. “Compasses?”
“Not merely geographical ones.” Eva stepped closer, forgetting the constable until Quinn raised one hand. She stopped. “Paths overlap. Certain objects detect weak points between places. Rifts. Portals. Crossings.”
“Magic doors,” Bell said.
Eva looked irritated. “If reducing a complex and dangerous phenomenon to two words helps you retain it, yes.”
Bell almost smiled.
Quinn pointed to the empty circle on the counter. “What was there?”
Eva peered past her. Her face drained of colour.
“A Veil Compass.”
“You’re certain?”
“Small brass casing. Protective sigils on the face. Usually green around the hinge from oxidation. Sable kept one on display, though he never sold it.”
“Why not?”
“It was crafted by a Shade artisan. It points toward the nearest supernatural rift.”
Quinn glanced at the surrounding instruments, every needle aimed toward the corpse.
“And all of these?”
“Imitations. Lesser instruments. Some find ley intersections. Some detect cursed thresholds. One allegedly points toward whatever you most regret, though I’ve never seen it do anything but turn toward the nearest pub.”
“The Veil Compass is missing,” Quinn said. “Could it have opened a portal?”
“No. It only locates them.”
“Could a portal move a body?”
Eva looked at Sable. “Yes.”
Bell exhaled. “There’s our bloodless route.”
Quinn looked down at the victim’s clean bare feet. A man transported without walking. A wound delivered elsewhere, body passed through a rift, blood beginning to pool only after arrival.
Too neat.
“If the killer used a portal,” she said, “why remove his shoes?”
Eva answered quietly. “They may not have.”
Quinn met her eyes.
“Crossings aren’t always clean,” Eva continued. “Sometimes objects don’t come through. Especially iron, salt, living tissue—”
“Shoes?”
“Depends what they were made from.”
Quinn studied the corpse’s ankles. Around the right one ran a thin black line, no wider than a thread. She crouched again. The mark circled the skin perfectly . Not a bruise. Not dirt.
A cut.
Bell saw it. “Wire?”
“No.” Quinn examined the left ankle. The same line, slightly higher. “A boundary.”
She remembered a case three years ago. Morris’s coat severed at the sleeve without a blade mark on the skin beneath. His radio found twenty metres from the rest of his equipment, still transmitting his breathing after he was gone .
She pushed the memory down hard enough to feel it resist.
“His shoes didn’t fail to cross,” she said. “His feet crossed through something that closed at the ankles. Whatever was below remained behind.”
Eva stared at her. “You’ve seen a severance line before.”
Quinn rose with care. “No.”
The lie came easily. Eighteen years helped with that too.
She turned toward the back wall, where Bell had reported the cold patch. The tiles there were cracked and stained, half hidden by a hanging rug patterned with silver eyes. Quinn pulled the rug aside.
Cold touched her face.
The wall behind it bore a soot-black oval about the size of a doorway. At its centre, someone had drawn a spiral in wet blood. The mark shone under the lamps.
Bell swore.
Eva stepped nearer, then halted. “That’s not a portal.”
“You just said—”
“I said rifts exist. That is a ward.”
Quinn examined the spiral. Its turns matched the carving on the knife handle.
“What does it ward against?”
Eva’s green eyes moved to the body.
“Something trying to get out.”
Silence settled over the stall. Beyond the curtains, a charm clinked against a pipe. Once. Twice.
Quinn checked her worn leather watch . The second hand had stopped.
The portable lamps dimmed.
Every compass needle in the stall swung away from the corpse and snapped toward the black oval on the wall.
All except one.
From inside Eva’s satchel came a soft metallic tick.
Quinn’s gaze dropped.
Eva clutched the bag against her side.
“Open it,” Quinn said.
“It’s books.”
“Open it.”
“Harlow—”
Quinn went still. “I didn’t tell you my first name.”
Eva’s mouth closed.
Bell’s hand moved toward his baton, then reconsidered and settled nearer his radio.
Quinn stepped forward. “Put the satchel on the counter.”
For one beat, Eva did nothing. Then she eased the strap over her head and set the worn leather bag down. Books pressed against the flap from within. She undid the buckle.
The smell of old paper rose into the cold air.
Eva removed a notebook, two clothbound volumes, a packet of pencils, and a pair of white archive gloves. At the bottom lay a small brass compass furred with verdigris. Protective sigils crowded its face.
Its needle pointed straight at the blackened wall.
Bell looked from the compass to Eva. “You picked a poor evening for coincidence.”
“I didn’t steal it.”
“Then how did it get in your bag?”
“I don’t know.”
Quinn watched her hands. No tremor now. Fear, yes, but focused fear. Eva had expected danger in the Market. What she had not expected was the compass.
Quinn picked it up by its edges. The casing was cold enough to ache through her glove. A brown-red thumbprint stained the lid.
Not Eva’s. Too broad.
Sable’s blood.
The needle quivered , then rotated away from the wall. It swept across Bell, the photographer, the constable.
It stopped on Quinn.
Behind her, something knocked from the other side of the tiles.
Three deliberate taps.
Quinn’s heart contracted once, violently.
Three years vanished. Rain on a warehouse roof. Morris laughing at her for over-tightening the strap of her watch . Then darkness, the smell of scorched stone, and three taps from inside a wall where no room existed.
The compass needle held steady on her chest.
Bell said her name, but his voice seemed far away .
Another three knocks sounded behind the tiles.
Eva stared at Quinn with dawning horror. “It isn’t pointing at you.”
Quinn forced air into her lungs. “No?”
“It’s pointing through you.”
She turned.
Across the aisle, beyond the green curtains and the crowded stalls, the covered mirror stood beneath its fallen muslin. In its exposed strip of glass, the Market did not appear.
A man stood there instead.
Rain slicked his dark hair to his forehead. His police coat hung open over a blood-soaked shirt. His face was pale, strained, unmistakable.
DS Morris raised one hand to the glass.
His lips formed a single word.
Run.
The black oval behind Quinn split down the middle with the sound of a long, slow breath.