GRENUN: When The Air Killed Us

Chapter 13: The Roofline

The iron rungs of the fire escape are slick with freezing salt water and a fine layer of gritty black ash.

Every time I haul my weight up another foot, my leather work shoes slip against the wet metal, sending a violent shudder straight up my thighs. My right arm aches from pulling my soaked, water-logged body upward, but my left arm remains locked around the yellow emergency box, pinning the case tightly against my ribs.

SKRRR-HHHH. SKRRR-HHHH.

Inside my Dräger respirator, my breath is a hot, wet rasp that rattles against the internal purge valve. Sweat pools at the base of my chin inside the lower silicon seal, sloshing against my skin with every head motion. The lower viewports of my mask are half-fogged with condensation, forcing me to tilt my head back just to see Mara’s dark, water-dripping boots four rungs above me.

"Keep moving, Silas!" Mara’s voice barks through her mask's exterior speaker, sounding flat and tinny against the howl of the coastal wind. "Don't look down at the alley! Don't look at the water!"

I can't help it. I glance over my left shoulder.

Thirty feet below us, the narrow alleyway behind the pharmacy has vanished completely. The sea has swallowed it whole. Black, oil-slicked floodwater churns between the brick walls, carrying broken wooden crates, shattered window frames, and the swollen corpses of drowned street dogs.

And drifting right along the surface of that black current is a low, rolling carpet of pale green mist.

It hangs four inches above the water line like thick, sickly smoke. Even from thirty feet up, I can see the vapor pulsing—expanding and contracting in soft, rhythmic waves that match the rising swell of the tide.

I haul myself over the top iron rail of the ladder, throwing my weight onto the gravel roof of the apothecary building.

I drop to my knees, gasping violently through my filters. PHUT-CLACK. The purge valve flutters as I force a deep, dry breath into my burning lungs. The charcoal canisters on my jaw buzz with a low, vibrating hum that vibrates straight through my teeth.

Mara is already on her feet, standing near the brick edge of the roof with her 12-gauge shotgun held low across her waist.

The rain hits us sideways. The wind coming off the Baltic Sea is a freezing, sulfur-laced wall that tears at our coats, whipping black rainwater across our clear facepieces.

Above us, the sky remains a flat, terrifying ceiling of bruised grey ash—a sunless, suffocating lid that turns the mid-morning world into an endless twilight.

To the south, across a two-mile expanse of drowned residential rooftops, the industrial ridge rises out of the gloom like a dark spine of rock. At its highest peak, barely visible through the driving rain, stands the red-and-white steel skeleton of the regional broadcast tower.

It looks a hundred miles away.

"The sea wall collapsed completely," Mara says, pointing her gloved hand toward the harbor district.

Through the grey drizzle, the entire lower city of Greifswald is gone. Streets have become ocean channels. Gas stations are submerged up to their signboards. The tops of overturned city buses stick out of the dark water like dead whales.

"The water isn't stopping," Mara continues, her hazel eyes darting across the roofline ahead of us. "If the tide rises another three meters, these three-story brick flats will be completely flooded. We have to stick to the interconnected rooftops along Fischerstrasse to reach the railway bridge."

"The bridge is open to the air," I say, my muffled voice echoing inside my mask. "If the wind drops, the green fog will settle right on the tracks."

"Then we run faster," Mara replies coldly.

She turns and begins pacing toward the north edge of the roof.

I scramble to my feet, adjusting the shoulder strap of the yellow box. The blue light leaking through the case's sealed seam has dimmed slightly, shifting from a bright sapphire to a steady, pale indigo.

I check the digital display monitor set into the top casing:

REGEN-4 NEUTRALIZER MATRIX: ACTIVE

CORE INTEGRITY: 91%

BATTERY LIFE: 70:42:19

AIRBORNE SCRUBBER STATUS: STANDBY (LOW DENSITY DETECTED)

Seventy hours. Seventy hours before the core burns out and becomes nothing more than ten pounds of useless titanium scrap.

"Silas!" Mara snaps, stopping five feet from the edge of the roof. "Look."

I hurry over to her side, keeping my boots flat on the slick gravel.

The building we are standing on is separated from the adjacent four-story residential block by a narrow six-foot gap—a dark, vertical drop that plunges straight down into the flooded alleyway thirty feet below.

Spanning the six-foot gap is a rusted iron fire escape walkway, its floor made of open metal grating.

Standing in the exact middle of that iron walkway is a man.

He isn't moving. He isn't holding onto the handrails. He stands perfectly still in the sideways rain, wearing a wet, dark blue police raincoat. His head is turned slightly upward, facing the sky, his mouth wide open.

Schlaf, Kindlein, schlaf...

The sound is faint, almost swallowed by the roaring sea wind, but it’s there. A thin, rhythmic hum that vibrates through the iron walkway, carrying straight across the wet gravel to our boots.

The officer’s face is a dull, waxy slate-grey. Dark, cord-like black veins bulge across his exposed neck, crawling up his throat and creeping into his jawline. His eyes are milky white—two blank, unblinking marbles staring up into the ash-clouded sky.

And from between his teeth, a thick, concentrated plume of pale green vapor escapes with every exhaled note, rising into the coastal wind before being swept sideways across the walkway.

He's guarding the bridge, the thought hits my brain like an iron spike. He isn't just standing there. The network positioned him at the narrowest choke point between the rooflines.

"Is he alone?" I whisper into my mask, pulling back half a step.

"No," Mara says quietly.

She points her shotgun barrel toward the far roof of the residential block across the walkway.

Standing along the concrete parapet of the higher building, lined up at six-foot intervals like terrifying stone gargoyles, are seven more figures.

An old man in a wet trench coat. A young woman in a yellow raincoat. A teenager with torn jeans. All of them standing perfectly erect in the storm. All of them facing our direction. All of them humming in silent, synchronized unison.

The pale green mist curling from their mouths doesn't blow away in the wind.

It forms a continuous, low-hanging cloud that rolls along the parapet of the far roof, cascading down the brickwork like a waterfall of toxic vapor, filling the narrow air space between the two buildings.

Sixty seconds.

If we cross that walkway, we will be stepping directly into a dense, eight-foot-thick wall of concentrated Regen-4 aerosol.

"We can't jump it," Mara says, her voice tightening behind her mask. "The drop from the fire escape to the roof below is ten feet. If you slip on the wet gravel down there with that box, you'll break an ankle."

"The shotgun," I say, looking at the 12-gauge in her hands. "Can you clear the walkway from here?"

"I can blow his head off," Mara replies, her hazel eyes locking onto the transformed officer. "But shooting him won't stop the air. His lungs will keep leaking fog until the thoracic pressure drops to zero. That takes four minutes after death."

Four minutes. We don't have four minutes.

Behind us, from the access hatch on the roof of the pharmacy we just climbed, comes a heavy metallic BANG.

The rusted iron hatch door bows upward.

BANG.

Someone is coming up the internal stairwell.

"They followed us through the pharmacy," I scramble backward, my heart hammering against my ribs so hard I can hear the pulse ringing in my ears. "Mara! The door behind us!"

BANG. SNAP.

The iron latch on the roof hatch snaps off. The square metal door flies open, slamming back against the gravel with a loud CLANG.

A pale, grey hand reaches out of the dark stairwell, gripping the lip of the concrete hatch housing.

It’s Jonas.

He isn't wearing his rubber gas mask. His leather jacket is torn at the shoulder, soaked with black rainwater. His grey face is completely covered in a dense network of thick, black, pulsing veins that branch across his cheeks and wrap around his forehead like a crown of thorns.

His milky white eyes lock onto Mara.

He steps out onto the roof, his boots crunching against the wet gravel. He doesn't carry his tire iron anymore. His arms hang loosely at his sides.

"Mara," Jonas hums. His voice is rich, clear, and terrifyingly gentle, carrying effortlessly over the roaring storm. "Why are you running up here? It’s so cold on the roof. Come back down to the shop. Leo is making tea."

Behind Jonas, two more transformed figures climb out of the dark hatch—a young girl in a blue school sweater and an elderly man with a bloody bandage wrapped around his head.

We are trapped.

To our back: Jonas and two Grenuns advancing slowly across fifty feet of open gravel.

To our front: an infected police officer blocking a six-foot walkway, backed by seven Grenuns cascading fog off the high parapet.

To our left and right: a thirty-foot drop into a drowned alleyway of churning black sea water.

"Silas," Mara says, her voice dropping all panic, becoming sharp, cold, and calculated. "The yellow box. Can you force the scrubber core into maximum override?"

"If I break the safety seal on the manual valve," I yell through my respirator, "it will purge thirty percent of the battery life in five minutes! It’ll burn out the titanium core!"

"Do it!" Mara snaps, racking a heavy slug into her shotgun chamber—CLICK-CLACK. "Or we die on this gravel in sixty seconds!"

I don't think. I react.

I drop to one knee on the wet gravel, shoving the yellow emergency box flat against the roof between my boots. With shaking, sweat-slick fingers, I flip open the heavy brass latches on the sides of the case.

The lid springs open four inches.

The electric blue light erupts into the grey storm like a flare, blinding my viewports in a flash of sapphire fire. The freezing cold ozone smell hits my mask intake instantly, so cold it turns my breath to thick white steam inside my facepiece.

I reach my bare right hand into the glowing interior of the box, grabbing the red manual override wheel set beside the titanium core.

WARNING: MANUAL PURGE OVERRIDE

AIRBORNE RADIUS EXTENDING TO 40 METERS

CORE DEGRADATION RATE: CRITICAL

I yank the iron wheel ninety degrees to the right.

WHIRRRRRR-BOOM!

A high-pitched, deafening electronic shockwave erupts from the yellow box.

It isn't a blast of fire. It’s a physical wall of pressurized, ultra-cold purified air that blows outward from the case in a visible, forty-meter sphere of shimmering blue mist.

The heavy green fog rolling off the high parapet ahead of us instantly shatters, its chemical particles neutralizing into harmless white water droplets that fall flat against the gravel.

The transformed police officer on the walkway staggers backward as the cold ozone sphere hits his chest. He opens his mouth to hum, but the hyper-purified air cuts off his chemical transmission, his lungs gasping uselessly against the sudden vacuum of toxic aerosol.

"NOW!" Mara screams.

She fires her shotgun straight past the police officer's head, the blast echoing off the brick walls as she charges headfirst across the iron walkway.

I slam the lid of the yellow box shut, locking the brass latches, haul the screaming, blue-glowing case up into my left arm, and sprint after her into the freezing, ozone-washed air.

Behind us, Jonas steps into the expanding blue sphere, his milky white eyes wide, his slate-grey lips parting as he takes his first breath of clean air since he tore off his mask.

And for a fraction of a second, as I plunge across the high walkway into the dark drizzle, I hear Jonas choke out a single, human word in his old, gravelly voice:

"Run."