The Warning Relay

I parked the pickup where the unmade forestry access track ended, close against a galvanised security fence secured with a padlock the size of my fist. The track stretched away behind us towards the A82, empty for as far as I could see. Nobody came to this part of the Great Glen in February unless they had to. I had to.

The work order said the transmitter at Site Golf Lima Echo 4, GLE-4, had dropped offline twice during the previous week. Standard winter trouble, probably. Ice on the lines or a breaker that needed nursing. I had done this sort of call perhaps fifty times.

Drive out from Inverness, check the basics, log the work, drive back. About four hours altogether if the roads were clear. I switched off the engine and sat there for a moment. My head felt as if someone had packed it with wire wool.

I had managed perhaps four hours' sleep, and two of those had been on the sofa after I passed out there at about 02:00 with a can of Tennent's Lager still in my hand. That was three nights in a row. Four if I counted the weekend. I needed to stop doing that.

The wind struck me the moment I opened the door. It came across the frozen loch to the east without meeting anything that could slow it. I pulled my woollen hat over my ears and zipped my high-vis jacket to the throat. The cold got in anyway.

It always did.

Euan Fraser was already out of the passenger side, standing by the fence and looking towards the path that led up to the relay hut. He did not seem in any hurry. His parka hood was up, his gloves were on, and he stood there as though we had come for a pleasant walk.

'Keys in the usual place?' he asked.

'Lockbox on the fence post. Code's in the binder.'

I retrieved the binder from behind my seat and turned to the site index. Golf Lima Echo 4.

The code was 7729. I entered it into the lockbox and took out the gate key and hut key, both attached to a carabiner with a faded plastic tag marked GLE-4. The gate opened without trouble. There was not even any ice on the hinges.

That was something.

The path to the hut ran for about 180 m through the trees, and snow had drifted across it in uneven waves. Nobody had been up there for some time. At the far end I could see the hut, a squat concrete-block box with a steel roof and a small aerial mast rising from its rear corner.

It looked exactly like every other Arqiva-maintained emergency-broadcast relay I had serviced. Plain, functional and cold, carrying Met Office warnings and civil-contingency announcements to people scattered along the Great Glen.

I started walking. The snow rose above my ankles in places, and the wind kept pressing against my back. My boots broke through the crust with each step. I watched the hut and tried not to think about anything else. That was easier than thinking about the headache, or the fact that I would have to do the same thing at another site the following day.

Euan followed a few paces behind, taking his time.

'You all right?' I called.

'Yeah. Just enjoying the scenery.'

There was no scenery beyond snow, trees and a grey sky. But that was Euan. He could make a call-out to a transmitter hut sound like a weekend away. I did not have the energy for it.

I checked my watch. It was 09:43. We were meant to be back in Inverness by 15:00, and Helen Ward had already sent me two messages asking for updates.

She did that on every call. She wanted to know when we arrived, when we began work, when we finished and when we left. I understood. She had a whole grid of contractors to manage and a dozen relay sites that could fail at any time.

Even so, it made every job feel like a countdown.

I took out my mobile and sent her a brief message.

'Arrived on site. Starting inspection.'

She replied in less than a minute.

'Copy. Report findings by 11:00.'

That gave me an hour and seventeen minutes. Fine.

The hut door was metal, painted white perhaps a decade earlier, with the paint peeling away in long strips. I unlocked it and pushed. It caught for a moment, then scraped open across the concrete floor.

It was warmer inside. Not warm, but warmer. About 5 degrees C instead of minus 9 degrees C. A small electric heater in one corner started automatically whenever the temperature dropped too far. It kept the equipment from freezing, but did little for anyone working there.

The hut was a single room, roughly 4 m square. Equipment racks lined the left wall: the primary transmitter, the backup transmitter, the power supply, the battery bank and a tangle of cables running between them. Against the right wall stood a small desk with a logbook, a clipboard and a dusty office telephone that probably no longer worked. The floor was bare concrete.

The only window was a narrow slot close to the ceiling, too high to see through. I dropped my pack by the door and took out the inspection checklist. Euan came in behind me, moving slowly, and set his gear beside mine.

'Smells like old electronics,' he said.

'Yeah.'

It did. Circuit boards, warm dust and stale, dry air. I was used to it. I switched on my torch and began at the top of the rack.

Visual inspection first. Burnt components, loose cables, anything obviously wrong. The primary transmitter appeared sound. Every indicator was green.

The backup was in standby mode and looked fine as well. I ran a hand along the power cables and checked their connections. Tight. No corrosion.

Euan was at the desk, leafing through the logbook.

'Last entry's from November,' he said.

'Nobody comes up here unless something breaks.'

'Looks as if something broke.'

'Looks that way.'

I moved down to the battery bank. It consisted of twelve deep-cycle 12 V batteries, arranged as three parallel strings, each string containing four batteries wired in series to provide 48 V. They sat on a wooden pallet to keep them clear of the cold floor.

I tested the first battery. 12.4 V. Good.

The second read 12.3 V. Also good.

The quiet had begun to trouble me. Not an absence of noise exactly. The equipment hummed and the heater rattled faintly. It was more the awareness that we were a long way from anyone else.

Usually I did not mind. I preferred working alone, if anything. That morning, though, the isolation seemed heavier than usual.

Probably the hangover.

I carried on. Euan leaned against the desk and watched me.

'You look tired,' he said.

'I'm fine.'

'You sure?'

'You've been a bit off all week.'

'I'm fine,' I said again.

He left it there. That was one of the things I liked about Euan. He knew when not to press.

I checked my watch again. 10:12. I needed to move faster.

I recorded the battery voltages in the binder, then checked the transmitter settings. Everything appeared normal. The frequency lock was sound. Output held steady at 50 W. The diagnostic menu showed no error codes.

So what was wrong?

I took out my mobile and opened the work order again.

Intermittent signal loss. Duration approximately fifteen to twenty minutes. Events recorded at 09:00 on 5 February 2026 and 14:00 on 8 February 2026. Today was 10 February 2026.

I frowned. Intermittent faults were the worst. If something was completely dead, you could trace it. If it failed only now and then, you either had to wait for it to happen again or reproduce whatever conditions caused it.

Up there in winter, the conditions were nearly always the same: cold, windy and remote.

I returned to the power supply and examined its logs. Two entries were marked in red, one for 5 February and another for 8 February. Both showed a brief fall in input voltage. Only a few seconds, but enough to knock the transmitter offline. When the supply returned, the transmitter rebooted and normal operation resumed.

So it was a power fault. Probably a poor connection somewhere between the main panel and the hut. That meant tracing the whole cable run, which meant going outside again. Brilliant.

I noted it in the binder and checked my watch. 10:31.

I messaged Helen.

'Primary inspection complete. Possible power-supply issue. Tracing external lines now.'

Her answer came quickly.

'Understood. Stay on schedule.'

Right.

I told Euan we needed to inspect the external line. He nodded and picked up his pack.

We stepped into the cold, and I locked the door behind us. The mains cable ran from a distribution pole roughly 90 m south of the hut. It was buried for most of that distance but exposed where it entered the building through conduit on the rear wall.

I went round the back and examined the conduit. There was no obvious damage and no build-up of ice. I removed the junction-box cover and inspected the connections. Everything was tight.

I followed the shallow trench marking the buried cable. Every few metres, I stopped to look for disturbed earth, subsidence or places where animals might have dug. There was nothing.

Euan walked parallel to me, a couple of metres to my left, saying little. The wind strengthened, and I drew my hood tighter. By the time I reached the pole, I had checked the entire run without finding a fault.

That bothered me.

If the problem was not a bad connection, it had to be farther upstream. In that case, it belonged to the regional distribution network operator rather than us. Helen would still expect me to confirm it before closing the ticket.

I returned to the hut. The wall clock inside showed 11:07. I had already missed Helen's deadline.

I sent another message.

'External line clear. Issue likely upstream. Monitoring transmitter for anomalies.'

She did not reply at once. That was unusual.

I sat at the desk and opened the logbook. Euan leaned against the equipment rack, drinking water from a bottle he had taken from his pack. He looked relaxed. I was not.

I turned back through the entries, searching for a pattern. Most pages were blank. A few carried notes from other contractors.

Replaced fuse A3.

Cleaned air filter.

Rebooted transmitter after lightning strike.

Ordinary work.

Then something occurred to me. The two dropouts, on 5 February and 8 February, had taken place at different times: 09:00 and 14:00.

If the fault came from the mains infrastructure, I would have expected it during periods of heavy demand, perhaps in the early evening when people had heating and cookers running. But 09:00 and 14:00 did not fit.

I stared at the records, trying to make sense of them.

The transmitter clicked.

It was a loud, hard sound, like a relay engaging. I looked up. The green indicator on the primary transmitter went dark.

Then it came back. Then it went dark again.

Euan straightened.

'What's it doing?'

'I don't know.'

The light cycled three more times: on, off, on, off, on. Then it stayed lit. The whole sequence lasted perhaps ten seconds.

I stood and approached the rack. The diagnostic menu remained open on the small LCD screen. I scrolled through the error log. A new entry had appeared.

Power interruption detected. Duration: 4 seconds.

But I had just tested the supply. It had been fine.

I checked it again. The voltage remained steady, with no fluctuations or recorded dropouts.

The transmitter clicked once more. This time its light stayed off for a full five seconds before returning.

Euan watched me.

'Is that normal?'

'No.'

I took out my mobile and checked the time. 11:14.

The transmitter clicked a third time. Off, on, off, on. It cycled as though somebody were operating a switch, but there was no switch being touched.

The supply was automatic. The transmitter was designed to run continuously unless it developed a fault or somebody shut it down manually. I had touched nothing.

I stared at the rack and felt something shift in my chest. Not panic. Just the quiet recognition that this was no longer routine.

The transmitter continued cycling. On, off, on again. Yet the supply reading stayed level. It did not make sense.

I took my torch from my pocket and crouched beside the pallet. Twelve deep-cycle batteries, grouped into three parallel 48 V strings of four 12 V units in series. I had checked them half an hour earlier. The individual readings had been normal: 12.4 V on the first battery and 12.3 V on the second, exactly what I expected from a standby bank on float charge.

I placed the multimeter probes on the first battery again.

11.8 V.

I blinked, checked the contact and tried again.

11.7 V.

That was wrong. A battery did not lose half a volt in thirty minutes unless something was drawing heavily from it.

I moved to the second battery. 11.6 V.

The third read 11.9 V.

The whole 48 V bank was sagging.

I stood and examined the panel above the power supply. The green mains-input light was on. The display showed a steady 230 V AC.

When the mains supply was healthy, the battery bank should have remained on float charge. It should not have been discharging at all.

'Euan.'

He looked up from the desk. He had been turning through the logbook again, probably searching for something sensible.

'The batteries are draining.'

He frowned, came over and looked at the multimeter in my hand.

'How fast?'

'Fast.'

I crouched and tested the fourth battery. 11.7 V.

'They've lost about half a volt in thirty minutes. All of them.'

'But we're on mains power.'

'Yeah.'

'So why are they draining?'

'I don't know.'

Euan scratched his cheek.

'Maybe the charger is offline.'

I pointed to the panel.

'It says it's supplying charge.'

'Then something's drawing from them.'

'Nothing should be.'

I stood and surveyed the rack. Primary transmitter, backup transmitter, power supply and cooling fan. The fan was not even running. It was only about 5 degrees C in the hut.

The total load should have been less than 100 W. The battery bank could have carried that for days without sagging so quickly.

I tested the first battery once more. It now read 11.6 V.

Euan saw my expression.

'That's not good.'

'No.'

The transmitter clicked. Its light went out for three seconds, then returned.

I watched the panel. Mains input was still green. The voltage remained at 230 V AC.

'Go and check the meter,' I said.

'Outside?'

'Yeah. Meter box is on the south wall. See how quickly it's registering consumption.'

Euan pulled his gloves back on.

'You think the load is going somewhere else?'

'I don't know what I think.'

I went to the desk and picked up the satellite phone from beside the logbook. 'I'm calling Helen.'

'She'll love that.'

'Probably not.'

Euan zipped his parka and went out. Cold air rushed through the doorway before the latch clicked shut, leaving me alone.

I switched on the satellite phone. It took a minute to acquire a signal, the bars appearing one at a time in the corner of the display. When it connected, I selected Helen's direct number and called.

It rang four times. I assumed she would not answer. She was probably in a meeting or dealing with another failed site.

Then the line clicked.

'Ward.'

'Helen, it's Callum. GLE-4.'

'Go ahead.'

Her voice had the clipped edge it always acquired when she was doing several things at once. I could hear another person speaking in the background and the indistinct noise of the Inverness office.

'We've got an unstable feed,' I said. 'The transmitter is cycling on and off. The power supply says the mains input is good, but the battery bank is draining quickly. Something is pulling load and I can't trace it.'

There was a moment's silence.

'Define quickly.'

'About half a volt from each 12 V unit in thirty minutes, across the whole bank.'

'That isn't normal.'

'No.'

Another silence. I heard her typing.

'Any error codes?'

'Only power interruption. Four-second dropout. But the panel shows steady voltage.'

'You've checked the external line?'

'Yes, before this started. It's clear all the way to the distribution pole.'

The next pause was longer. The typing stopped.

'Callum, I need you to hold.'

'What's happening?'

'Just hold.'

Her end went quiet, though the call had not disconnected. A faint hiss remained on the line, but she had muted herself.

I stood with the phone against my ear and watched the equipment rack. The transmitter light had steadied now, green and apparently normal. The power-supply fan, however, had started, which meant the unit was working harder than it should.

My watch showed 11:17.

Helen returned.

'Callum, are you still there?'

'Yeah.'

'Police Scotland's Highland control room is receiving calls.'

'What sort of calls?'

'People are reporting the warning tone. Multiple reports in the last twenty minutes. It keeps repeating on the broadcast frequency, but there is no announcement afterwards.'

Something tightened in my chest.

'We haven't keyed anything.'

'I know. That's why I'm trying to establish whether it's a local fault or something upstream.'

'The transmitter has been cycling,' I said. 'Maybe the reboot is triggering the tone.'

'Maybe.'

She did not sound convinced.

'How long before you can stabilise it?'

'I don't know. I've sent Euan to check the meter. If the load is external, I'll have to trace it, and that could take-'

'I need it stable, Callum. People think there's a civil emergency.'

'I'm working on it.'

'Work faster.'

The line went dead.

I put the phone on the desk. My headache had returned, throbbing behind my right eye. I should have eaten that morning. I should have slept for more than four hours. That part was my own fault.

I turned towards the rack.

The speaker mounted above the desk made a sound. It began low, almost a hum, then climbed into a high, piercing tone that filled the room. It held for three seconds and stopped.

I froze.

It was the civil-contingency warning tone used before severe-weather, flood or public-safety announcements.

We had not keyed it.

I crossed to the rack and checked the transmitter panel. There was no active input. No audio signal passed through the chain. The level meter lay flat and dead.

The tone sounded again at the same pitch and for the same three seconds. Then silence.

I looked at the speaker. It was a basic unit, about 15 cm across, fixed to the concrete-block wall with two screws. It was connected to the monitoring system so engineers could hear whatever the transmitter was broadcasting. If the transmitter sent something, the speaker reproduced it.

That was the entire arrangement.

But the transmitter was not sending anything.

I checked the diagnostics. No input detected. No audio source active.

The tone sounded a third time.

This time I felt it as well as heard it. It vibrated in my teeth and in the bones of my jaw. It no longer seemed to come from the speaker. It came from the air, the walls, everywhere and nowhere.

I stepped back.

The door opened and Euan came in, snow on his shoulders and his hood still raised. He looked at me, then at the speaker.

'You heard that?' I asked.

'Yeah. I could hear it outside as well.'

'Outside?'

'Only faintly. I thought it was coming from in here.'

He lowered his hood and brushed snow from his sleeves.

'The meter's racing.'

'How fast?'

'As if we're running an electric heater and an industrial kiln at the same time.'

He went to the rack and studied the equipment.

'None of this should be pulling that kind of load.'

'I know.'

He began to say something else, then stopped. He was staring past me at the wall.

I turned.

The LED clock above the desk had jumped to 11:31.

My watch said 11:18.

The wall clock snapped back to 11:18. Then it leapt forwards to 11:24, returned to 11:18 and settled there after a single blink.

Euan said nothing. Neither did I.

I stood watching the clock, feeling the day slide out from beneath me. All the rules I understood - voltage, current, load and time - were bending into something for which I had no language.

The warning tone sounded again, and I realised we were no longer repairing a transmitter.

I took the logbook from the desk. I thought I should record what we had seen: the clock jumping, the disagreement between it and my watch. Document everything. That was what you were meant to do.

I opened it at the next blank line. The last entry was mine, written about twenty minutes earlier when I recorded the battery voltages.

I took a pen from my jacket and began to write the time.

Then I stopped.

There was another entry beneath mine.

It was in my handwriting. I knew it at once: the same slant, the same shape of the capital M in Mercer, the same abbreviation I always used for transmitter.

I had not written it.

The date was 11 February 2026. Tomorrow.

I read it twice.

Replaced fuse links per regional directive. No improvement. Battery drain continues. TX cycling persists.

My hand remained suspended above the page, still holding the pen. I could not move. I could not look away.

Euan said something behind me, but I did not catch it. I read the entry again. The writing did not blur or shift. It was simply there, solid ink on paper.

I had written instructions to myself from a day that had not happened. Or I would write them tomorrow, after replacing fuse links we had not yet touched.

The pen slipped from my fingers and struck the desk.

'Callum?'

I turned. Euan was staring at me.

'Look at this,' I said.

My voice sounded flat.

He crossed the room in two strides and leaned over my shoulder. I pointed at the entry. He was silent for a long time.

Then he lifted the logbook, held it close and tilted it towards the narrow window, perhaps checking whether the ink was wet or whether the entry was some kind of trick.

It was not.

He set the book down with care.

'That's your handwriting.'

'Yeah.'

'You didn't just-'

'No.'

We stood there.

The transmitter clicked behind us. The warning tone rose from the speaker for the same three seconds. I did not flinch this time.

Euan rubbed his face with both hands.

'Right. Right, this is-'

The satellite phone rang.

I answered on the second ring.

'Mercer.'

'Callum, it's Helen.'

Her voice was taut, strained in a way I had never heard before. She did not wait for me to reply.

'Are you still seeing the cycling behaviour?'

'Yeah, and the batteries are still draining. We just-'

I looked at the logbook and left the sentence unfinished.

'It isn't stabilising.'

'Inverness is seeing similar activity at several relay sites along the Great Glen,' she said.

The words came quickly and sharply. Sites near Loch Ness, Invermoriston and Fort Augustus were all reporting intermittent signal loss and unexplained power demand.

I looked at Euan. He was watching me.

'How many sites?' I asked.

'Six so far. Regional operations know. They're coordinating with the distribution network operator, but nobody can identify the load.'

She paused. I heard papers moving at her end.

'I need you to shut the site down.'

That stopped me.

'Shut down the transmitter?'

'Shut down everything. Main breaker. Take GLE-4 offline until I receive instructions from regional.'

I did not answer at once.

Turning off the transmitter meant disabling part of the warning network. If there were a genuine emergency - a storm, flood or anything else - people in the area might not receive the announcement. That was the reason these sites existed. They were meant to remain live.

'Callum, did you hear me?'

'Yeah. I heard you.'

'The order comes from above me. I don't like it either, but we don't know what we're dealing with.'

Her voice softened slightly. It remained controlled, but I could hear the fear beneath it.

'Kill the power and get back on the road.'

'Understood.'

She ended the call without saying anything else.

I put the phone down. Euan was still watching me.

'She wants the whole site offline,' I said.

He nodded slowly.

'Makes sense if the other sites are doing it too.'

'Yeah.'

I went to the main electrical panel beside the rack. It was a grey metal cabinet perhaps 60 cm tall. I opened the cover. Inside was the main breaker, a heavy black switch in the upper position, with separate breakers below for the primary transmitter, backup unit, lights and heater.

I rested my hand on the main breaker.

I hated this part. I hated leaving a site dark. These transmitters were built to operate continuously. They were the final source of information for people when other systems failed.

Cutting the power felt wrong in a way I could not express.

But the order was clear.

I pulled the breaker down.

The transmitter's green light went out. The power-supply fan slowed with a fading whine. The overhead fluorescent tube died, leaving only pale grey daylight from the high window. The heater clicked off.

Silence.

I waited.

Then the warning tone sounded again.

It was fainter and more muffled, but unmistakable: the same three-second rise from a low hum to a sharp upper edge.

Euan turned towards the wall speaker.

'How is it doing that?'

'No power,' I said.

I stared at the rack. Every indicator and display was dark. The speaker could not possibly produce a sound.

The tone came again.

This time it did not seem to issue from the speaker, or not only from there. It came from deeper within the wall, as though it had entered the concrete blocks. It was more vibration than sound.

I closed the panel.

Euan stood perfectly still in the centre of the room.

'Callum, we should go.'

He was right. We should have left, driven back to Inverness and filed a report so that someone else could deal with it. That was what a sensible person would have done.

But I was not thinking sensibly.

I was thinking about the meter spinning too quickly, the batteries draining without an identifiable load, my handwriting in a logbook dated tomorrow and six relay sites along the Great Glen displaying the same impossible behaviour.

Whenever I lose control of something, I repair something smaller. That is what I do. It is what I have always done.

'We need to test the backup generator,' I said.

Euan blinked.

'What?'

'If the mains feed is causing this, we can prove it by running the site from a stable supply independent of the grid. The generator is outside. Self-contained diesel unit. No connection to the mains network.'

'Helen told us to shut it down and leave.'

'She told us to shut down the transmitter. We have.'

I was already moving towards the door.

'This is only a backup-system test. We make sure it's operational before we go.'

It was a thin justification, and we both knew it.

Euan did not move.

'You genuinely think that will help?'

'No,' I said. 'But I need to know.'

He stared at me for several seconds, then sighed and raised his hood.

'Diesel can is in the pickup. I'll fetch it.'

I took the hut key from my pocket and unlocked the narrow metal cabinet beside the desk. Inside were a coil of extension cable, a toolbox, spare fuse links in a plastic case and the generator's detachable starter cord, wound into a loop.

I took the cord and went outside. Euan followed.

The wind hit me first, stronger and colder than before. It came from the frozen loch to the east and carried a pressure I could not name. It was not merely cold or wind. It was wrong.

The trees surrounding the hut stood too still despite the air pushing against us. Their branches did not stir. No loose snow drifted across the ground. Everything felt compressed, as though the air itself had acquired weight.

I stopped on the concrete slab outside the door. Euan came alongside me, his hood pulled tight and his hands thrust into his pockets. He looked at the trees, then at me.

'You feel that?' he asked.

'Yeah.'

The forest felt as though it were waiting. Watching.

I had spent six years working at remote sites, sometimes alone for hours among trees while I inspected equipment, ran cable or cleared vegetation. I knew isolation. I knew silence.

This was neither. It was something pressing in from every direction, a presence without a visible source.

The warning tone sounded inside the hut behind us. The walls muffled it, but it remained audible and wrong.

I made myself move.

The backup generator stood behind the hut in a small wooden enclosure with a sloping roof. I followed the side of the building, my boots crunching over frozen snow and the starter cord held in one hand. Euan went the other way, towards the pickup and the diesel can.

I rounded the corner and stopped.

The generator enclosure was open.

I had locked it on my previous visit three months earlier, during a routine maintenance inspection. I always locked it. Now its door hung partly open, with the padlock dangling from the hasp.

The padlock itself was still closed and locked. The screws holding the hasp to the door frame had been pulled free of the timber.

I stood looking at it while the wind pressed against my back.

The trees did not move.

I heard Euan's boots behind me and the slosh of diesel in the yellow can. He came to my side and saw the door.

'Huh,' he said.

I did not answer.

I pulled the door fully open. A faded yellow Pramac diesel generator stood inside on its platform, about the size of a large suitcase, with a manual starter and integral fuel tank.

I had serviced it in November. I had filled the tank, checked the oil and run it for twenty minutes to make sure it started and carried load cleanly.

It looked undamaged. There were no animal nests and no sign that anything had been disturbed.

Except that the fuel cap was off.

The tank was full.

I looked again at the enclosure door. The padlock remained secured, but the hasp had come away from the wood. The screws were not lying on the ground and their holes were not stripped.

The screws were simply gone.

The places where they should have entered the frame looked clean, as if they had never held anything.

I turned towards the front of the hut.

That was when I saw the sky.

A green smear stretched across it from east to west, perhaps thirty degrees above the horizon. It was not bright, only a pale wash against the grey daylight. It resembled the aurora I had seen many times in the Highlands: a thin ribbon of green suspended above the hills.

But it did not move.

The aurora always moves. It shifts, pulses and folds through itself.

This remained fixed.

I watched it for perhaps fifteen seconds. It did not alter at all.

The air felt heavy, like the pressure before a thunderstorm but colder and sharper. I could feel it in my chest whenever I breathed. The headache behind my right eye grew worse.

The forest had become completely silent.

Not peacefully quiet. Dead.

There was no rush of wind through the branches, no distant bird call, no creak of timber and no snow slipping from the pines.

Nothing.

The wind was still blowing. I could feel it against my face and tugging at my jacket, but I could no longer hear it.

I looked down at the snow outside the generator enclosure.

My own boot prints were clear where I had rounded the hut, their tread regular and their spacing ordinary.

There were other prints as well.

Bare feet.

They came from the fence line, roughly 20 m away where the trees grew denser, and led directly towards the hut. They did not meander or circle. They crossed the snow in a straight line and stopped at the front door.

Someone had stood immediately outside the hut, barefoot in minus 9 degrees C.

The prints were narrow and smaller than mine. Each toe was sharply defined. There was no hesitation in the gait, no shortening of the stride from pain, just steady steps through snow cold enough to maim bare skin.

I returned to the front of the hut and crouched beside the prints at the threshold. They faced the metal door directly, both feet together and parallel, as though someone had stood to attention.

Or listened.

There were no prints leading away.

I heard Euan returning from the pickup through the trees. He carried the yellow diesel can in one hand, his hood still raised.

He stopped when he saw me crouched by the door.

'What is it?'

I pointed.

He looked at the footprints and said nothing for several seconds.

'Those weren't here before,' he said.

'No.'

'That's impossible.'

'Yeah.'

He put down the diesel can and walked slowly around the prints, taking care not to touch them. Then he looked towards the fence line and followed the trail with his eyes.

'Someone walked here barefoot.'

'Looks like it.'

'In this cold?'

'Yeah.'

'And then just stood here.'

I rose. My knees cracked.

'That's what it looks like.'

Euan stared at the prints for a few seconds longer, then lifted the diesel can.

'Let's test the generator and get the hell out.'

I did not argue.

We returned to the enclosure. Its door still hung open, the locked padlock attached to the loosened hasp. Inside, the faded Pramac diesel generator sat on its platform. It was about ten years old, its yellow paint chipped and dulled by weather.

I had serviced it three months earlier: oil, fuel filter and air filter. It had run perfectly.

I refitted the fuel cap, then checked the tank and supply line. The tank was already full, so the yellow can remained sealed beside Euan's boot. I engaged the pre-heat control, set the decompression lever and fitted the detachable starter cord into the manual starting assembly.

The first pull produced nothing. The engine turned against compression but did not catch.

I reset the decompression control and pulled a second time. Again the engine turned without firing, the cord snapping back into my hand.

On the third attempt it caught. The engine coughed, stumbled and ran roughly for perhaps three seconds, sending a puff of black diesel smoke from the exhaust. Then it settled into a steady mechanical rumble.

I adjusted the run control and let it warm.

The sound was normal, perhaps slightly louder than I remembered, though the wooden enclosure amplified it.

Then the lights in the hut came on.

From where I stood, I saw the glow through the narrow window slot: pale fluorescent light spilling into the grey day.

I had left the main breaker off. I had pulled it down myself ten minutes earlier.

The lights could not have power.

I looked at Euan. He stared at the hut, the unopened yellow diesel can still beside him.

'You left the breaker off,' he said.

'Yeah.'

'You're certain?'

'I'm certain.'

The generator continued to run, smooth and steady. I did not touch its controls.

I hurried to the hut, pulled open the door and went inside.

Every indicator on every equipment rack was lit.

The primary transmitter showed a full row of green LEDs across its front panel. The backup unit beside it was in standby, its indicators glowing amber. All three status lights on the power supply were lit: mains input, battery charge and DC output. The diagnostic screen shone bright blue while white text streamed across it.

It looked as though the station was broadcasting at full power.

I stepped closer to the rack and watched the screen. Numbers passed in a continuous loop. I recognised them at once.

Coordinates. 57.0916 North. 4.7132 West. This site.

GLE-4. They were the exact coordinates printed in the site documentation kept in the pickup.

The numbers scrolled away and new text appeared.

STAY ASLEEP.

It remained for three seconds, then repeated.

STAY ASLEEP.

Then the coordinates again. Then the message.

Over and over. I stood watching until it had completed three cycles. My mouth was dry. The headache had spread from behind my right eye across my entire forehead.

Euan came in behind me. He saw the screen.

'What the hell is that?'

'I don't know.'

'Is it transmitting that?'

I checked the VU meter on the front panel. The needle sat at zero. There was no audio input and no modulation. The transmitter was lit as if it were running, but the meter showed nothing going out.

'I don't think so,' I said.

'Then what's it for?'

I did not answer. I reached for the primary transmitter's power switch, a red toggle at the lower right of the front panel, and pushed it down to the off position.

Nothing happened. The lights stayed on. The screen kept scrolling.

I toggled it again.

Still nothing.

I tried the backup unit. The switch moved, but its lights did not respond.

There was an emergency stop button on the power supply, a large red mushroom button beneath a clear plastic cover. I had never used it. It was meant to kill everything instantly, isolating the 48 V battery bank and shutting down all DC output.

I flipped up the cover and pressed it. The button clicked, travelled perhaps a centimetre, then sprang back out.

I pressed it again.

Click. Pop.

It felt as though it were no longer connected to anything. The screen continued to scroll.

STAY ASLEEP.

'Callum.'

Euan's voice was tight. He stood beside the door, looking through the gap.

'We need to leave. Right now.'

I turned away from the rack.

'Yes.'

I took the satellite phone from the desk and pushed it into my jacket pocket. The logbook was still open at the entry in my handwriting dated 11 February 2026, the following day. I left it there.

I followed Euan outside and pulled the door shut behind me. I did not bother locking it.

The faded Pramac generator was still running behind the hut, its steady diesel rumble cutting through the dead silence of the forest. Euan began walking towards the path leading back to the galvanised security fence and the forestry access track.

I followed. We had gone perhaps ten paces when Euan stopped so abruptly that I nearly walked into him.

'Callum.'

He did not move. He was staring straight ahead along the path.

I stepped beside him and looked.

The gate was gone.

The galvanised fencing remained on both sides, running east and west between the trees. But the gated section, the part we had opened with the key from the lockbox perhaps an hour earlier, had vanished. There were no posts, no frame and no gate.

The chain that had been looped through the fence had been cut cleanly through one of its links. The two ends hung against the mesh. They were neither rusted nor worn, merely severed.

Beyond the place where the gate should have stood, there was no track.

The roughly 180 m unmade forestry access track we had driven along from the junction was gone. In its place stood untouched snow and trees. Dense Scots pine and birch crowded together, their branches heavy with snow. Old growth, the sort of forest that would have taken decades to fill the space.

It had not been there that morning.

I stared at the trees where the track should have been, at the severed chain and at the fence ending on either side of a gap with no gate.

Euan turned slowly, looking at the hut, the trees and the green smear that still hung motionless across the sky.

'Callum,' he said quietly, 'where's the track?'

I did not answer. I had no answer.

We walked anyway. The pickup was gone and the track had vanished, but I thought we could follow the route it ought to have taken.

Euan stayed close on my left. I could hear his breathing and the crunch of his boots through the snow. There was little else.

The warning tone continued behind us, fainter now: three seconds rising from low to high, then silence, then the same sequence again. Beneath it, another sound began.

A hum.

It was low and constant, and it did not come from the hut. It rose from the ground itself. I felt it through my boots, my knees and my chest. It was not quite a sound. It was closer to pressure.

I kept my eyes on the trees ahead. The fence line should have been about 18 m away, followed by the gate and then the access track running back towards the A82. It was a simple route. I had walked it an hour earlier.

The hum grew louder.

I looked back. The hut stood behind us, close. Too close.

We had been walking at a reasonable pace for perhaps two minutes and should easily have covered 45 m, yet the concrete-block walls looked no more than 9 m away. The aerial mast rose straight and narrow against the green smear in the sky. I could see the generator shelter behind the hut, its door still hanging open.

'Callum.'

Euan's voice was flat.

I turned forwards again. He had stopped walking. He raised an arm and pointed through the trees.

I saw the hut.

The same concrete-block walls. The same steel roof. The same aerial mast. But the orientation was wrong. I was looking at it from the side rather than the front. The narrow window faced east instead of south. The generator shelter stood on the left rather than the right.

I stood there. Euan stood beside me. Neither of us spoke.

Two huts. The same site and the same structure, standing in different positions.

I took my mobile from my pocket. Its screen lit cold and bright in my hand. The time was 11:43.

I checked my watch.

Its hands showed 11:26.

I stared at both for perhaps ten seconds, then shook the watch and held it to my ear. It was still ticking in a steady rhythm. There was nothing wrong with the movement.

'Check your mobile,' I said.

Euan pulled his out and tapped the screen several times.

'Frozen.'

'What does it say?'

'12:00. Exactly noon.' He tapped it again. 'No, wait. The seconds are moving. It's only the hour and minute that are stuck.'

I checked mine again. It now read 11:44.

My watch still showed 11:26. The second hand swept smoothly and continuously around the face.

The hum from the ground deepened. I felt it in my teeth.

I pulled out the satellite phone, a heavy black brick with a thick antenna. I extended it and switched it on. The display took perhaps fifteen seconds to acquire a signal.

Three bars. Good enough.

I selected Helen's direct number and called. It rang four times.

She answered on the fifth.

'Ward.'

'It's Callum. GLE-4.'

'Callum.'

Her voice sounded strained, as it had during the earlier call. Tight and controlled, but with something underneath it.

'You're still on site?'

'Yes, we're...'

I stopped, trying to decide how to explain it.

'We've got a situation.'

'Define situation.'

'The track's gone. The pickup's gone. We can't get back to the gate.'

Silence on the line. Only faint static within the hum of the satellite connection.

'Helen?'

'Callum, what are you talking about?'

Her voice returned sharper.

'You never arrived.'

Something cold dropped through my chest.

'What?'

'Your tracker shows the pickup parked near the Esso service station on the A82 at Fort Augustus. It's been there for the past two hours.'

'That's not possible. We've been at the site since 09:43. I texted you when we arrived.'

'I didn't receive any text from you this morning.'

I pulled the mobile from my pocket and opened the message thread. My text from 09:43 was still there.

Arrived on site. Starting inspection.

Beneath it was her reply.

Understood. Report findings by 11:00.

I put the satellite phone back to my ear.

'I'm looking at the thread now. You replied at 09:44.'

'Callum, I'm looking at my phone. The last message I have from you is yesterday's, confirming the work order.'

The hum grew louder.

Euan turned in a slow circle, looking from one hut to the other. His hood remained up and his hands were in his pockets.

'We're at the site,' I said. 'Golf Lima Echo 4. We've been here all morning.'

'The system says you never checked in. The gate log shows no access today.'

I looked back at the first hut, then ahead at the second. The same structure. The same equipment. Two places at once.

'Helen.'

'Get back on the road. Return to Inverness. We'll debrief when you arrive.'

'The road isn't here.'

Her voice became very quiet.

'What do you mean, it isn't there?'

'I mean we walked to where it should be and there are only trees. No gate. No track.'

The line went silent again, longer this time. I counted perhaps eight seconds.

'Callum, listen carefully. Find the access track. Get in the pickup. Drive back to the A82. Do not stop. Do not investigate anything else. Just get back onto the carriageway.'

'I'm telling you, the track isn't-'

She disconnected.

I stood with the satellite phone against my ear while the hum travelled through my boots and into my legs. Then I lowered it and looked at Euan.

'She says we're not here.'

'Where does she think we are?'

'Fort Augustus. Near the Esso.'

Euan pulled back his hood. His face looked pale.

'That's about forty minutes south of here.'

I nodded.

He looked at the hut ahead and then at the one behind us.

'So what do we do?'

I had no answer. The track was gone. The pickup was gone. Helen said we were not there.

But the huts were real. The snow was real. The cold was real.

I turned towards the nearer hut, the one ahead of us with the wrong orientation.

'We go back inside,' I said.

Euan did not argue.

We walked towards it. Nine metres, then six. This time the distance felt right. Normal.

The door came into view, the same heavy steel door with the narrow window above it. I reached for the handle.

It turned.

I stopped. I had locked it. I always locked it. Standard procedure. You did not leave a national emergency-broadcast transmitter site unsecured.

I opened the door anyway.

The warmth struck me first. Not the roughly 5 degrees C maintained by the automatic heater. Proper warmth, perhaps 21 degrees C or more.

The air was thick and damp.

Then came the smell. Wet wool, strong and musty, entirely wrong for a relay hut that should have smelt only of concrete and cold electronics.

I stepped inside.

The layout matched, although its orientation was reversed: equipment rack on the left, desk on the right, concrete floor and narrow window. The lights were on.

Every panel indicator glowed. The diagnostic screen still scrolled through the coordinates and the message.

STAY ASLEEP.

Over and over.

On the floor beside the desk, half submerged in a puddle of melted snow, stood a pair of boots. They were neither mine nor Euan's.

Brown leather work boots, perhaps size nine or ten. The laces were tied. Snow packed into their treads was melting across the concrete.

Beside them lay a handheld microphone of the type connected to the transmitter for manual broadcasts. Its lead was stretched taut to the rack. The push-to-talk button had been bound down with several layers of duct tape.

It was continuously keyed.

I crossed the room and crouched beside it. The tape was fresh, with clean edges and no dust.

I removed a glove and worried at one corner with my fingernail until it lifted. Then I peeled the tape away in one long strip.

The button sprang up.

The tone continued.

I stood holding the tape in my hand as the tone climbed from low to high for three seconds, fell silent, then began again.

Euan moved beside me.

'Callum.'

I looked at him. He pointed towards the window.

Beyond the fence, where the trees grew dense, something moved.

Something large and heavy was forcing its way through the branches with a noise like timber breaking. It did not stop.

Euan reacted first. He stepped past me and flicked the overhead light switch down. The fluorescent tube died, leaving the room dim. Only the green and amber rack indicators and the faint grey daylight through the window remained.

I crouched beside the rack and shifted closer to the glass. The slot was about 15 cm high and 60 cm wide, set high in the wall near the ceiling. I had to angle my head to see outside.

The trees beyond the fence were moving. They were not swaying. They were being pushed aside.

Something enormous forced its way between them. Branches snapped with cracks like rifle shots. I heard bark scraping and the low creak of trunks bending under its weight.

Then it stepped into view.

A red-deer stag. That was the first shape my mind gave it. The bulk was wrong for one, far too great, but there were the shoulders, the long head and the branching antlers.

Its legs bent incorrectly. They folded backwards at joints that should not have moved that way. The lower sections were too long, the upper ones too thin. Yet it moved smoothly, without hesitation or any trace of a limp.

Then its head emerged fully.

It lowered its face towards the window, and I stopped breathing.

The muzzle was there, but compressed, as if someone had pressed a stag's skull into wet clay until its features blurred. There were no eyes. I could see the hollows where sockets should have been, but the skin over them was smooth and unbroken. No lids. No lashes. Only hide stretched tightly across the empty shapes beneath.

Its nostrils worked, flaring as it drew in the air through long, deliberate breaths.

I thought of dogs scenting food or blood. This was not that. It was smelling for current. For the hum in the cables. For whatever frequency the transmitter had been driving into the ground.

I knew that. Do not ask me how.

Euan spoke quietly behind me.

'There are flares in the pickup.'

I did not move or look away from the window. The creature tilted its head slowly, as though the movement hurt it.

'We run for it,' I said, keeping my voice level. 'Get into the pickup. Drive until something looks familiar. Call for help from somewhere stable.'

'All right.'

I stood. My knees cracked. The headache behind my right eye pulsed hard enough to blur my vision for a moment.

Euan moved to the door and put his hand on the handle. I made sure the satellite phone was secure in my jacket pocket. We left the logbook and everything else.

'Go.'

Euan wrenched open the door and we burst outside.

The cold struck first, then the wind, then the ground.

My boots sank, but not into snow. Something gripped the soles and dragged at them like wet cement before it had set. I tried to lift my foot. It rose slowly, heavily, with the surface clinging to it.

I looked down.

The snow had vanished.

What I had thought was snow, what had been snow ten minutes earlier, was now ash. It lay packed, dense and grey-white, its surface smooth. It was warm. I could feel that warmth through the leather of my boots. Not hot, merely warm, as though it had lain in sunlight for hours.

Euan stumbled beside me. His arms flew out for balance and he caught himself on one knee.

'What the hell?'

The stag-thing slid around the corner of the hut.

Slid was the only word for it. Its legs moved, but the motion was wrong, too fast and too smooth, as if the creature travelled on rails.

I pulled the vehicle emergency flare launcher from my jacket pocket. It had an orange plastic grip and held a single cartridge.

Euan tried to stand, but his boots were stuck. He pulled hard and the ash answered with a wet sucking noise.

The creature was 4.5 m away, then 3 m.

I raised the launcher, aimed at the centre of its chest and fired.

The flare struck it and burst.

Red light flooded the clearing, bright enough to hurt. The creature stopped.

I saw its skin, pale and mottled, stretched tightly over its malformed frame. Beneath it were shapes.

Hands.

Dozens of them. Small human hands pressing outwards against the membrane as if trying to escape.

The flare burned against its chest and the hands pushed harder. The hide bulged and rippled. Then the creature turned away from the light and towards Euan.

No.

I dropped the launcher, caught Euan's arm with both hands and hauled.

He came free.

His boot did not.

It remained upright in the ash, its laces still tied, like a marker. Euan hit the ground on his side and I dragged him back to his feet.

His socked foot came down in the ash. He hissed through his teeth but kept moving.

We ran.

The pickup stood ahead, 18 m away, then 14. I could see it through the trees: the white Ford Ranger with the contractor's logo on the door, parked exactly where we had left it.

The gate was open. I did not remember opening it on our way out.

Euan reached the driver's door first and pulled it open. I ran around the bonnet and tried the passenger side.

Locked.

'Euan!'

I slapped the window.

'Unlock it.'

He leant across the seats and pressed the button. The lock snapped up. I climbed in and slammed the door.

Euan already had his hand beside the ignition.

There was nothing there. No keys.

'Where are they?'

His voice cracked.

'I had them.'

I searched my jacket and trouser pockets. Nothing.

'I had them when we arrived.'

Euan looked at me, then past me through the passenger window.

I followed his gaze.

There, in the ash about 3 m from the pickup, lay a key ring: a silver carabiner, three keys and a faded blue plastic tag marked with the site code in permanent ink.

Mine.

They rested in the ash as if they had lain there for months. Years.

I threw open the door and stumbled out. My boots sank again, but I kept moving. I seized the ring.

The metal was ice-cold.

I scrambled back into the pickup and shut the door. Then I pushed the key into the ignition and turned it.

The engine caught, turned over once and died.

'Come on.'

I tried again.

Click.

Click. Click.

The battery was dead.

'That's impossible,' Euan said. 'We just drove it here.'

I stared at the dashboard. The radio display was dark. The clock was dark. Everything was dark.

Drained.

Behind us, the hut door swung open.

There was no wind and no hand upon it. It simply opened.

The warning tone surged, louder than before. It did not come from a loudspeaker. It came from everywhere: the ground, the trees, the air itself.

Then I understood.

The hut was not the source. It was the mouth.

The stag-thing, the ash and the tone were hurting us, drawing us back towards the signal.

'Stay low,' I said.

Euan stared at me.

'What are you doing?'

I took the handheld radio from the centre console, a cheap Motorola unit. Its battery indicator showed full.

'Stay here. Lock the doors.'

'Callum?'

I was already outside.

The mast stood about 15 m behind the hut, a standard three-section structure rising roughly 18 m. Guy wires ran down to concrete anchor points.

I ran. The ash tugged at my boots, but I kept moving as quickly as I could.

At the mast's base stood the lightning-arrester box, a grey metal enclosure secured with a padlock. I pulled at the lock.

It held.

I kicked the box. The hasp bent and its screws tore free.

Inside were junction blocks and thick copper grounding cables running from the mast into conduit.

I pulled a separate red hand flare from my jacket, part of the works pickup's safety kit. I twisted off the cap and struck the head against the ignition strip.

It caught.

Red flame sprang out, fierce enough for me to feel the heat against my face. I drove it into the wiring.

The insulation blistered and blackened. The copper beneath began to glow.

The hum in the ground spiked. I felt it in my teeth and through my skull.

There was movement behind me.

I did not turn. I held the flare against the grounding cables and forced it deeper.

The stag-thing charged.

I heard it coming. I felt the air move.

The mast groaned.

The sound of metal under stress rose high and sharp. One of the guy wires snapped, whipped past my head and buried itself in the ash.

The mast tilted, slowly at first, then fast.

Eighteen metres of steel and aluminium crashed into the trees. It struck the frozen pines with a noise like thunder. The cables stretched, snapped and tore free from the hut. Sparks poured from the junction box on the rear wall.

The warning tone stopped in the middle of a note.

It was simply gone.

The air felt empty and hollow.

I stood with the flare still burning in my hand. Beneath my boots, the ash cooled and hardened. In three seconds it changed from warm and clinging to cold and brittle.

I dropped the flare and stepped back.

The stag-thing had vanished.

The hut door hung open. Its interior was dark. No lights. No indicators.

I returned to the pickup.

Euan was now in the passenger seat, hunched over and staring at his socked foot. I climbed behind the wheel, put the key in the ignition and turned it.

The engine started on the first attempt.

I looked beyond the bonnet.

The forestry access track was there beyond the gate, cleared through the snow, our tyre marks impressed along it as though it had never vanished.

I selected drive and pressed the accelerator.

We rolled forwards, passed through the gate and joined the track. I did not look back.

Euan sat silently beside me, his breath fogging the windscreen. He kept staring at his foot.

I drove hard, pushing the Ranger to 60, then 70 km/h, dangerously fast for an icy unmade track. The trees blurred past.

Ten minutes later, we reached the bend where the track curved towards the A82. My mobile buzzed. Two bars of signal.

I took out the satellite phone and passed it to Euan.

'Call Helen.'

He extended the antenna and dialled. It rang four times.

'Ward.'

I took the phone from him.

'It's Callum.'

'Callum. Where the hell have you been? I've been trying to reach you for three hours.'

'The mast failed. The site collapsed. Conditions were unsafe. We're heading back.'

Silence.

Then she said, 'What do you mean, the mast failed?'

'It came down. The lightning arrester shorted. The whole structure's compromised. We had to evacuate.'

'You brought down a national emergency-broadcast transmitter?'

'It came down on its own. We were securing the site when it happened.'

There was another silence.

'I'm opening an incident response. You'll need to file a full report when you get back. This could cost you the contract, Callum. You know that.'

'Yes.'

'Get to the Inverness office. Don't stop. Don't speak to anyone. Come straight here.'

She ended the call.

I set the phone on the dashboard.

Euan shifted beside me and rubbed his ankle through his sock.

'Are you all right?' I asked.

'My boot's gone.'

'I know.'

'It was tied. The laces were tied.'

'I know.'

He looked at me.

'What was that thing?'

I did not answer. I kept driving.

The A82 appeared ahead, tarmacked, gritted and normal. I turned north towards Inverness.

I checked the rear-view mirror.

The trees already concealed the site. The hut, the fallen mast and everything around them had disappeared behind the curve of the track.

But the green smear remained in the sky, horizontal and perfectly still, like a fixed light that refused to go out.

I kept my eyes on the road and drove.