The Londrivar Guard headquarters had not been built to intimidate.

  It had managed the effect all the same.

  It was a grey stone building on the boundary between Lower Londrivar and the Upper Quarters — geographically neutral, which in practice meant it belonged entirely to neither world and was distrusted by both. Three storeys, narrow windows, a staircase too wide for the door it led to. Steam pipes emerged from the roof at regular intervals, giving the building the permanent appearance of something about to explode, unhurriedly.

  Crowe climbed the staircase without looking up.

  He knew the interior well enough not to need to pay attention — the front desk to the left, the central corridor leading to the offices, the rear stairs to the second floor where Maren had his room. There were guards who recognised him and guards who didn't. Those who recognised him let him through. Those who didn't tried to stop him and learned, from Crowe's expression, that there were more productive choices available to them at that moment.

  Maren was in his office with the door open and the expression of someone who had slept less than Crowe.

  The room was small and functional — desk, two chairs, a filing cabinet with the middle drawer that never closed completely. On one wall, a map of Londrivar covered in pencil markings that Maren had been updating for years and never fully erased, creating layers of overlapping investigations like geological strata.

  — You went to the Institute — said Maren when Crowe entered. Also not a question.

  — Ashcroft recognises the notation system from Voss's diagrams — said Crowe, sitting in the chair on the other side of the desk without being invited. — It appears in three documents in the archive. Two are accessible. The third is under Guard restriction.

  Maren was quiet.

  — I need authorisation for the third document — said Crowe.

  — What's the record?

  — Ashcroft knows the title. — Crowe paused. — Register of disappearances associated with discontinuity phenomena. Londrivar, last forty years.

  The silence that followed had a different texture from Maren's usual silences. Not the silence of someone thinking — the silence of someone who had already thought and hadn't liked the result.

  — You know what that document is — said Crowe.

  — I know it exists — said Maren. There was a careful distinction in the words. — That's not the same thing.

  — Maren.

  The inspector stood. He went to the window — narrow like all the others in the building, overlooking a side alley where two pigeons were arguing about something over a steam grate. He stood with his back turned for a moment.

  — Three years ago — he said, with the voice of someone measuring each word before releasing it — an inspector on the second floor opened an informal investigation. He began connecting closed cases. Disappearances without a body, without a witness, without apparent motive. All at specific addresses across the city. All with small strange details in the reports that most people overlooked.

  — What happened to him?

  — He was transferred — said Maren. — To a station at the northern edge of the city. A district with no movement, no relevant cases. — A pause. — Voluntarily, according to the record.

  — According to the record — Crowe repeated.

  Maren turned.

  — The document you want to see is part of what that inspector had compiled before the transfer. It was deposited at the Institute as a historical archive because no one knew what to do with it and no one wanted to destroy it openly. — He returned to the desk but didn't sit. He stood with his hands resting on the surface, looking at Crowe with that expression that wasn't exhaustion but resembled it. — If I give the authorisation, my name goes in the access register.

  — I know.

  — And if someone checks that register —

  This story originates from Royal Road. Ensure the author gets the support they deserve by reading it there.

  — Maren — said Crowe, with a pause before and after the name that functioned as a frame. — Aldric Voss went to Ashcroft three weeks ago. Asked the same questions I asked today. Three weeks later he vanished from a sealed room. The document the inspector compiled lists disappearances with the same characteristics over forty years. — He let that settle for a second. — This is not an informal investigation. This is a pattern.

  Maren stood still for a moment.

  Then he opened the middle drawer of the desk — not the one that never closed, the lower one — and took out a block of official forms. He wrote with the large, deliberate handwriting of someone being careful about what they are doing, signed it, tore off the sheet, and pushed it across the desk.

  — Temporary access authorisation — he said. — Valid for forty-eight hours. — A pause. — Use it well.

  Crowe took the paper. Folded it carefully.

  — There's one more thing — he said.

  — Of course there is.

  — The nameless client in Voss's notebook. Calibration service, three days before the disappearance, no value recorded and no signature. I need to find him.

  — How do you find someone with no name?

  — Through the service — said Crowe. — Calibration of an unconventional instrument is not common work. Voss had a known speciality. If someone came to him for that specific service, that person knew his reputation. Which means they move in circles where Voss's reputation was known. — He stood. — Watchmakers, instrument makers, academics in applied science. I need a list of names from those circles.

  Maren looked at him with the expression that appeared when he was calculating the work he was about to accept.

  — That will take time.

  — I have forty-eight hours of authorisation — said Crowe. — You have the same.

  He left before Maren could respond, which was a strategy he had learned to use in moderation — it worked precisely because it was rare.

  The Institute was twenty minutes on foot.

  Crowe went on foot.

  Not to save time — there were faster ways — but because he needed the journey. It was on the stretches between places that the mind worked best, without the weight of a specific environment demanding attention. The streets of the Upper Quarters were wide and relatively clean, with that expensive silence Crowe had always found slightly artificial — as though money didn't merely buy comfort but also bought the absence of sound.

  He thought about Voss.

  A sixty-two-year-old watchmaker who had spent weeks developing a notation system derived from documents nearly a century old. Who had received a nameless client to calibrate something unconventional. Who had been excited, according to Ashcroft — not frightened, excited — when he confirmed what he suspected.

  Like someone who had found the answer to an old question.

  And then he had seen the interval. And then he had vanished.

  Crowe stopped at a crossing, waiting for a carriage to pass. Steam rose from the pavement grates in slow spirals, and for a moment — a brief moment, which he registered and filed away without dramatising — he had the sensation that the steam was not rising.

  It was descending.

  He blinked. Looked again. The steam rose normally, as it always had.

  He kept walking.

  The headache behind his left eye pulsed once, sharply, and then returned to its previous dull weight.

  Ashcroft was waiting with the document already on the desk when Crowe arrived.

  The folder was thin — fewer than thirty pages by the look of it — bound in black leather with no title on the cover. There was a red wax seal, already broken, which meant it had been opened before. Probably by the inspector who had compiled it, probably for the last time before the transfer north.

  Crowe sat. He placed Maren's authorisation on the desk. Ashcroft collected it without examining it — trust or tact, probably both — and left the office, closing the door behind him, which was unusual enough to be a deliberate gesture.

  Privacy offered without being asked.

  Crowe opened the folder.

  It was twenty-seven pages.

  The first eight were introduction and methodology — the inspector had been methodical, which Crowe respected. Clear criteria for including cases: disappearance without a recovered body, without a witness to the moment, an address with a record of prior or subsequent anomalous physical phenomenon, and at least one instance of the symbol — the circle with the line — at the location or among the person's belongings.

  The remaining nineteen pages were cases.

  Crowe read them slowly, which was not his natural habit but was the correct approach for this material. He read with his notebook open beside him, making minimal annotations — dates, addresses, details that recurred.

  There were twenty-three cases in forty years.

  Twenty-three people who had disappeared from enclosed spaces without a physical trace, at addresses distributed across the city, with the symbol present in every case and physical phenomena that the official reports had catalogued as equipment failure, collective hallucination, or simply ignored.

  Crowe reached the last page.

  The inspector had written a conclusion — brief, three paragraphs, with the restraint of someone who knew he was documenting something that would be difficult to defend. The last sentence was the only one he had underlined:

  The disappearances do not follow the pattern of a crime. They follow the pattern of an experiment.

  Crowe stared at that sentence for a long time.

  Then he closed the folder carefully, as though the care mattered.

  Twenty-three people in forty years. All of them had found the interval. All of them had been found by it.

  And Aldric Voss was the twenty-fourth.

  Outside, Londrivar went about its business of appearing normal. The chimneys smoked, the gears ground, the rail carriages cut through the fog with their regular whistles.

  The city worked as it had always worked.

  And beneath all of it, in the gaps between one gear and the next, something watched.

  Crowe was certain of that now.

  He didn't know what it was yet. He had no vocabulary for it, no framework, nothing beyond twenty-four cases and a sentence underlined by an inspector who had been transferred north for having come too close.

  But he knew he was getting close.

  And for the first time in a long while, he wasn't entirely sure that was a good thing.