GRENUN: When The Air Killed Us

Chapter 14: The Railway Trestle

My leather work shoes slam onto the slick concrete of the four-story residential roof, sending a spray of dirty rainwater over the parapet.

Behind us, the high-pitched turbine whine of the yellow emergency box slowly drops an octave, its internal cooling fans struggling against the violent strain of the manual purge. The intense sapphire glare leaking through the plastic seams dims from a blinding flare back down to a steady, rhythmic pulse.

WARNING: OVERRIDE CYCLE COMPLETE

CORE INTEGRITY: 64%

BATTERY LIFE: 41:18:05

Seventy-two hours just got cut down to forty-one. Nearly half our remaining air supply, burned up in five seconds of desperation on a open gravel roof.

SKRRR-HHHH. SKRRR-HHHH.

I drag a ragged, burning breath through my Dräger respirator, my ribs aching as if someone hit me with a sledgehammer. The air inside the facepiece tastes metallic, scorching the back of my dry throat like powdered rust. I clamp my left arm tighter around the yellow case, the hard plastic handle biting into my palm through my wet leather glove.

Mara is ten paces ahead of me, her black tactical coat streaming with rainwater as she sprints along the narrow concrete ledge toward the western edge of the roofline.

"Don't slow down, Silas!" she yells through her mask speaker, her voice competing with the roar of the Baltic wind. "The blue pulse only neutralized the immediate aerosol! Once the local air currents clear the ozone, the fog will fill the choke point again!"

I glance back over my shoulder for half a second.

At the far end of the iron walkway, the blue sphere of scrubbed air is already collapsing. The pale green mist rolling off the upper parapets rushes back into the vacuum like a toxic wave, wrapping around the grey, motionless figures standing on the ledge.

Jonas is gone—swallowed by the dense yellow-green haze that settles over the iron walkway like a heavy shroud.

I turn my head away, choking back the bile rising in my throat, and force my legs to keep moving.

We reach the western edge of the residential block. Below us lies the iron spine of the regional railway trestle—a massive, two-track steel bridge that spans three hundred yards across the flooded industrial basin, connecting the low-lying coastal neighborhoods of Greifswald to the elevated granite ridge of the industrial sector.

The sea has claimed the ground beneath the trestle entirely.

Fifty feet below the iron girders, a dark, violent river of black floodwater rushes inland, carrying torn rooftops, crushed cars, and floating trees toward the bay. The steel support pylons vibrate under the sheer force of the current, sending a low, continuous rumble up into the iron tracks.

Spanning the tracks is a rusted steel catwalk—narrow, unshielded, and completely exposed to the sideways coastal rain.

"The catwalk is our only path across the basin," Mara says, dropping to one knee near the edge of the roof parapet to check the drop.

The steel ladder leading down from the roof to the railway track has sheared off its bottom anchors, dangling four feet above the rusted iron ties.

"If we drop down to the tracks," I say, my voice raspy and dry through my intake valve, "we're trapped between the steel trusses. There's no cover if the wind drops and the gas settles over the rails."

"There's no cover up here either," Mara snaps, turning her head to glare at me through her water-slick viewports. "Look at the ridge."

I follow the line of her black-gloved finger.

On the far side of the railway trestle, where the tracks curve upward toward the granite slope of the industrial district, three figures stand beneath the ruined concrete signal tower.

They aren't wearing civilian clothes.

They are wearing heavy grey tactical suits, complete with reinforced Kevlar chest plates and full-face respirator helmets. But their masks aren't sealed. The heavy glass viewports of their helmets are shattered, hanging loose from their locking collars.

Across their grey, waxy necks, thick black veins pulse beneath the wet rubber of their tactical suits.

Regen Enforcers.

The private corporate security force assigned to guard the upper bio-domes on the ridge. They were equipped with military-grade rebreathers, yet they didn't survive the leak. The gas got to them anyway.

The three transformed enforcers stand side by side on the raised signal platform, their hands resting loosely on the slings of their black submachine guns. They don't raise their weapons. They don't take aim.

They simply open their mouthpieces, and even through the thirty-mph wind tearing across the open basin, the coordinated harmony of their hum reaches us across the steel trestle.

Schlaf, Kindlein, schlaf...

The sound doesn't just travel through the air—it travels through the iron girders of the bridge. The very steel beneath our feet begins to hum with the exact acoustic frequency of the lullaby, sending a micro-vibration up through the soles of my leather boots.

My vision shudders. The sharp edges of the iron girders blur into double images.

Sixty seconds.

If three civilian Grenuns could expand their fog radius by breathing in sync, three corporate enforcers with high-capacity lung reserves will turn that three-hundred-yard railway bridge into a solid tunnel of concentrated poison.

"They're locking down the bridge," I choke out, my sweat-slicked fingers tightening on the handle of the yellow box. "Mara... they're using the iron structure to amplify the transmission."

Mara doesn't answer immediately. She unslings the 12-gauge shotgun from her shoulder, checking the side-saddle shell carrier attached to the receiver.

Three heavy slugs left. Two high-velocity buckshot rounds.

"We don't cross the open catwalk," Mara says, her hazel eyes narrowing behind her clear visor as she looks down at the heavy steel girders running beneath the tracks. "We crawl inside the hollow structural truss under the rail bed. The steel frame will break the wind, and the yellow box will keep a five-meter bubble clean while we move."

"And if the scrubber core fails halfway across?" I ask.

Mara looks me dead in the eye, her voice dropping into a flat, deadly whisper.

"Then we jump into the river."

She doesn't wait for my agreement. Mara swings her legs over the parapet wall, grabs the dangled iron ladder with both hands, and drops four feet onto the wet wooden ties of the railway track.

I take a deep, dry drag of charcoal-scrubbed air—SKRRR-HHHH—clamp the yellow emergency box against my chest, and follow her down into the open iron frame of the trestle.