Sea monster legends have haunted world’s deepest waters for centuries—whispers of serpentine shadows beneath still the thrashing waves of the deep ocean, creatures that never surface yet never sleep. In this creature feature short horror story, we explore a chilling encounter beneath the haunting Cinder Bay Sea—a breeding trench where folklore and fear meet. Inspired by cryptid sightings, leviathan myths, and deep sea horror, “Marked by the Deep: A Sea Monster Legend” drags you into the abyssal dark where something ancient waits… and breeds.
If you enjoyed the oceanic terror of LOOK AT ME—a ghostly tale set at sea—this story plunges deeper into the sea, where horror and folklore meet. Read on. But don’t hold your breath.
Chapter 1: A Creature Feature Folklore Wrapped in Pain
They say dreams are a conduit to a reality beyond the bounds of imagination, a beacon to a destiny that lies not so far from the reach of an ordinary man.
But to answer its call is to open an ancient box, unknown in its origins, and the menacing horrors it holds within.
The clock read 1.15 am when I woke up again in a puddle of sweat. Sure, my studio apartment was a cramped dump, but the autumn chill should’ve balanced those temperature scales.
Sighing, I reached for the remote control under my pillow and flicked the TV on, hoping the human voices would quell the horror that was building in my head.
Megan, the local hot news anchor, was on with a sombre face as she said, ‘The fish of the Cinder Bay Sea appear to have disappeared as local fishers complain of yet another week of zero catches. Local scientist blame the ENSO cycle…’
‘Yeah, yeah. ENSO my sweet butt. It’s the N’Gahari, and the Research Institute knows it,’ I responded, letting the TV drone on in the distance.
I peeled myself off the wet and sticky sheets and sat by the bedside, my eyes set upon the picture frame on my nightstand.
‘Jamie…’ I sighed.
My 2-year-old boy. His mother claimed custody after I lost my job at the Marine Research Institute six months ago. They said I was crazy, spending millions in tax-payer money chasing a mythical sea creature lodged in folklore and fiction. Maze, my wife, took the kid and left after I lost my job, refusing that I see my boy. I took her to court, but the jury decided I was too unfit… mentally, to raise a child.
I shook the thought from my head, remembering how hot and damp I’d got. Dragging myself out of bed, I stood by the only window in the room, kicking the lump of dirty laundry aside and shoving the shutters open. I closed my eyes and took in the cool midnight air, taking a deep and slow breath as I savoured the sweet elation of my calming, troubled senses.
But even as I closed my eyes, I could see them. The hideous conglomerate of searching, green, glowing eyes, floating in the abyss. I can still hear its soft, insidious voice hissing my name in the distance, ‘Jace. Come to me, Jace.’
Maybe I am losing my mind, I thought.
A loud ringing ensued in my head, followed by a sharp pain behind my eyeballs. I cried out at the piercing sensation and held firm to my temples, hoping to squeeze the pain through the sockets of my eyes. My knees wobbled under my weight, so I fell onto them, waiting for the torment to subside. And subside, it eventually did, leaving vestiges of pain floating in my head as I recovered from the excruciating agony.
I staggered back to my feet, leaving the window open, and reached for the bathroom door next to the window. The tiles were cold under the soles of my bare feet as I held onto the sink and reached for the medicine cabinet behind the bathroom mirror. I grabbed a bottle of Tylenol and emptied the last pill into the palm of my hand before closing the cabinet and tossing the pill down my gullet. Feeling it stick to my throat, I opened the tap for some water, but only a low droning sound came in response.
Cursing, I swallowed some saliva and felt the fat pill course its irking way down my dry throat, sticking in my chest a little before disappearing in the churning acids of my empty belly.
Groan.
That was my churning stomach. I was hungry, and there wasn’t so much as a fridge in the room. Just some old pizza in a box by the foot of the bed where I thought I’d seen a rat scurrying about as I came in the previous night.
I grunted and made my way there, sitting myself on the floor where I reached for the funky slice of pizza and took my first bite, ignoring the smell and taste as it broke into chunks inside my mouth. The rat came out from under the bed as I chewed. Smiling, I tore a piece and laid it on the floor for the rodent. It grabbed hold of the piece of pizza and gnawed, and for a second, I could’ve sworn it smiled back at me.
‘Well, well, well,’ I scoffed. ‘Jace Navarro. Diligent father and glorious marine biologist turned underwater welder. I’ve already lost everything else, so why not lose my mind?’
My appetite quelled at the thought, so I walked to my desk, thinking about the constantly repeating nightmare that had plagued my mind for almost a year. A tape recorder sat on the desk. I grabbed hold of it and pressed play.
A crackling sound came before the shivering voice of an old man came on.
‘Dr Elias Trent, 1964, entry number 192. Another dead body turned up from the Cinder Bay Sea today. There were no visible wounds, but his eyes were black. Bulged. And the body was… hollowed out-’
I pressed fast forward and listened to the tape buzz and whirr before pressing play again.
‘N’Gahari – that’s what the locals call the creature. There are no drawings of it. No photographs. No skeletal remains. Just a distinct pattern. Every few decades, the fish vanish. Divers report green light flashes by the Cinder trench. They say the creature doesn’t kill its victims. It marks them from afar, reeling them with vivid nightmares, and excruciating headaches until, finally, they lose their minds or-’
Static followed before the tape clicked stop.
Static followed before the tape clicked stop.
‘I’ve lost way too much over this,’ I declared, looking at my dive equipment hanging off the wardrobe doors by the corner of the room. ‘I need answers.’
Chapter 2: Sea Monster Legend in the Abyss
The vast, starless night harboured an ominous aura as a moored dingy yawed and swayed to the rolling ocean waves underneath me. The icy air stung at my skin as I changed into my dry wet suit. I shivered as the icy ocean spray scalded my skin, and I wished I’d had the revelation of changing back when I was still on dry land.
I had an inkling not to plunge into these depths alone at this time of night, but something was wrong with me. Wrong with my body. The headaches and nightmares had plagued my nights long enough. It cost me everything. I needed answers.
Once and for all.
I sat by the boat bulwark and checked my equipment, ensuring my BCD, weights, and tank were snug, and that the dive gauge, radar, and computer were all working well. Fitting a Goodman handle with the camera and dive lights onto my hand, I clasped two extra flash lights to the D-rings on my BCD shoulder straps and did a quick blow test through my rebreather.
I was ready.
I pulled the snorkel over my eyes and rolled backwards, plunging with a loud splash into the murky waters of the dark and vast Cinder Bay Sea.
My descent was slow at 5 meters a minute, taking extra precaution since I was alone. The dim ambient light disappeared almost immediately as I started my descent, forcing me to use the torch light on my Goodman handle. Its light penetrated the abyss, exposing a thick cloak of nothingness that enveloped my body as I descended deeper into it. The silence was eerie at this hour, without a single creature in sight to stir the water column or cruise by the beam of light from my torch.
I checked my dive computer: 6 meters.
I descended some more, feeling the pressure build in my ears, occasionally stopping to rest and decompress. Though I chose a dry wet suit for this expedition, the chill in the water still penetrated the foamed neoprene, sending shivers through me with every breath. But I braced, cautious not to exert myself and empty my tank before my expedition was over.
13 meters.
The radar in my dive computer was pinging now, and I knew I was close. I slowly panned the light torch around, hoping to catch a familiar glimpse of the caves I failed to map out before losing my job at the Cinder Bay Marine Research Institute.
The radar in my dive computer was pinging now, and I knew I was close. I slowly panned the light torch around, hoping to catch a familiar glimpse of the caves I failed to map out before losing my job at the Cinder Bay Marine Research Institute.
I still couldn’t find it.
15 meters
The water swayed, and I’d gone deeper than I’d expected. The pressure down here was crushing, and I struggled to move my limbs in the thick, icy water.
The water swayed, and I’d gone deeper than I’d expected. The pressure down here was crushing, and I struggled to move my limbs in the thick, icy water.
17 meters.
The pressure grew worse, and despite decompressing my ears repeatedly, I worried they would rupture at any moment. I panned the light beam around once more, the radar on my dive computer pinging louder in the water.
The pressure grew worse, and despite decompressing my ears repeatedly, I worried they would rupture at any moment. I panned the light beam around once more, the radar on my dive computer pinging louder in the water.
There it is.
The cave was massive as it came into view, its towering mouth devouring me whole as I swam through. I turned the radar off and blasted my light beam ahead, tapping the camera’s on switch as I ventured deeper into the cave.
The cave was massive as it came into view, its towering mouth devouring me whole as I swam through. I turned the radar off and blasted my light beam ahead, tapping the camera’s on switch as I ventured deeper into the cave.
The darkness in there was heavier, and the silence much more ominous. It was as though I’d unknowingly stepped into another dimension, where the abyss ruled with an iron fist.
The cave grew narrower the deeper I swam. I tried keeping my kicks slow and calm, cautious not to exert myself in the viscous, inky waters.
Something stirred, and I paused. A barred spine shot across the cave up ahead, where it broke off into a T-junction of sorts.
Got you.
Got you.
I followed the creature, venturing deeper into the cave. A dim green glow shimmered in the distance, and as I approached, rhythmic vibrations pulsed in my suit. My view grew better as I approached the green luminosity, illuminated better by the beam of light on my Goodman handle.
Soon, I was swimming over glowing green orbs, their light pulsing faintly in the water. They lined the floor and walls of the cave as they guided me to an opening, a giant chamber where more orbs lined the floors and walls by the thousands. Some were intact, and some had cracked open. They were like… eggs.
I was in a nest.
Another stir caught my eye – a green fin torpedoing from a cracked egg into another cave way to the far right. I flashed my camera in that direction, but I missed it.
Another stir caught my eye – a green fin torpedoing from a cracked egg into another cave way to the far right. I flashed my camera in that direction, but I missed it.
The rhythmic vibrations grew stronger in my suit. A shift in the water pressure registered through my body, and a shiver coursed down my spine. But this wasn’t the chill in the water… no. It felt like someone… something was right behind me. I felt its eyes burning in the back of my skull.
I slowly turned around, panning my flashlight to see it. The mere sight immobilised me, freezing the blood inside my veins and sending my pumping heart in a frenzy.
Those eyes… those green, glowing amalgamation of knowing eyes. Each one was the size of a soccer ball set upon a serpent-like face, its skin translucent, giving a glimpse of the flowing veins beneath that pulsed with a light shade of green. A double line of dark, spiny ridges ran along the length of its face, settling just above its flared nostrils. I watched in horror as the flesh between those ridges parted and folded into itself, revealing animated mandibles that rubbed and clicked against each other. Countless concentric rows of translucent needle-like teeth – some straight, some barbed backwards – twitched in clusters, lining behind the mandibles, leading to a dark hollow where a green glow pulsed and oozed a thick fluid that clouded the water. A shiver ran through me as countless double-headed serpents slithered through and swam towards me.
No.
They weren’t serpents They were forked tongues, like a snake’s, but they were so many. They curled, twitched and lashed over and around my suit, searched me, scanning me from head to toe.
They weren’t serpents They were forked tongues, like a snake’s, but they were so many. They curled, twitched and lashed over and around my suit, searched me, scanning me from head to toe.
I wanted to scream. I wanted to punch those tongues away. And I wanted to swim away… but the giant’s head was right at the entrance from which I came.
I was trapped 17 feet underwater in a cave no one knew about. This was my end, I was sure of it.
I braced as the giant creature wrapped its tongues around my right leg; the pressure growing by the second. The glowing eggs grew brighter inside the chamber, and I sensed more cracking behind me.
This is it, I thought. My time is now.
The creature’s mouth grew wider, its needle-like teeth and mandibles vibrating, and seemingly rotating, in a hypnotic display behind the green, cloudy hue. I immediately covered my ears, steeling myself for a sharp pain as a telepathic scream tore through my head. Reeling in agony, I doubled over as more of the baby serpents encircled me, slithering over me as they swam in a frenzy of their own.
The pain was too much, and right then, something popped in my ear, and I blacked out.
Chapter 3: A Dark Ending
The darkness was cold. It was thick. Heavy. But surprisingly forgiving as I woke up dipped deep inside of it. A ringing persisted in my head, and I found it hard to breathe through the mouthful of a re-breather fitted into my mouth.
I’m underwater, I gasped, my mind trailing back to reality.
My Goodman handle was gone, and so was the flashlight fitted into it. The extra flashlights were still on my chest D-rings, and I thanked God for the common sense of taking backups. I unclasped one and clicked it on, unleashing a beam of light that revealed a cave lined with cracked eggs, each flowing with a green, glowing goo. Rubble tumbled underneath me as I pushed against a round rock set upon the floor. I panned my light there and felt my soul depart my body.
That wasn’t rubble. And that round rock wasn’t a rock at all.
They were… bones. Skulls, femurs, carpels, and pelvises. Some were whole, white and fresh, some were blackened and plagued with waving algae, and some had crumbled to dust and fragments.
I felt something wiggle inside me and push out of my mouth. Something warm and acidic crawled up my oesophagus, and I gagged into my rebreather. Without even thinking, I launched myself out through the cave I came.
I kicked fast, checking my gauge, which showed a dangerously low air supply in my tank. Soon I was out in the open, and the deco buoy was the last thing on my mind as I began my ascent. My dive computer was cracked, so I had no idea how fast I was rising through the water column. Visions of the creature infiltrated my mind, and its unsettling jaw with rows of sharp, spiny teeth. And its babies, and how they wiggled over me, their slimy bodies writhing against my neoprene. Some on my arm, some on my leg, some in my hair. I could still feel their slime on my face.
I choked and coughed blood into my re-breather. My chest hurt, and for a moment, I thought my lungs would burst inside my chest.
But I didn’t care. I needed to get out of there.
I cried out loud when I breached the surface, the nurturing light of dawn washing over me as I spat out the re-breather and gasped for fresh air. Once again, I thanked God when I saw my dingy rolling over the waves close by, and I swam to it, hauling myself onto the deck. I slowly peeled the equipment off me, taking comfort in the abating claustrophobia. It wasn’t long before I was lying in my boxers, bathing under the warm morning sun and lulled by the rocking boat over the rolling ocean waves.
I’m lucky to be alive. I thought, sighing in relief.
And as I lay there, something prickled my thigh – a dull annoyance I decide I’d check later. But the prickle grew to a stabbing pain, forcing me to sit up and check.
There was a barnacle fixed on my skin.
But I was wearing a suit, I thought. How did that get there?
I tried touching it, and it was rough to the touch, so I pulled at it. The numbing pain shot back through my thigh, and I let go immediately.
I suddenly remembered. This was the leg the creature grabbed with its tongues down there.
Panicked, I grabbed the knife in my backpack and positioned the blade over my skin. Steeling myself, I grabbed my crumpled shirt off the deck and bit into it, counted to three, and sliced through, chopping a slice of flesh off my thigh and the damned creature with it. The pain doubled this time, and my muffled screams filled the salty air as I covered my leg. I puffed and huffed, willing the pain to subside as I uncovered the wound.
Oh, dear God. I remarked, staring in shock at what lay underneath my skin.
A tiny tentacle wriggled from the mouth of the wound.
Again, I felt something acidic climb up my food pipe and hurled over the deck. A stabbing pain shot through my stomach, sending me reeling over the boat deck. My gut grew bigger, rising and falling in rhythmic pulses. I cried out loud as the pain grew worse, clutching it with a squeeze, hoping the pressure would ease the ache.
That’s when I felt it, something wiggling underneath my skin. It sent ripples across my pulsing stomach, brushing against my hand. It was hard. My screams filled the morning horizon again as I stretched and curled into myself, digging my heels into the floor and kicking the air. I turned on my back and laid on my stomach, sitting and lying down, but no matter what position I tried, the pain persisted, worsening by the wake of every second.
Acid burned my throat as it rose up my gut, and again, I vomited over the deck, expelling dark bile into the blue waters. But as I did, I saw sharp spines break the surface, circling the boat. The green, serpent-like creature slithering underneath the surface. And it wasn’t alone. They spanned the water as far as my eyes could see.
The pain shot through my belly once more, and more screams escaped my lungs. The ripples in my stomach became more rapid. It felt like a knot of snakes slithering, wriggling and writhing inside me, tearing and snapping at my flesh from the inside out. Again, I hurled, getting on fours, expelling blood this time as something crawled up my chest and into my throat. I punched my chest, hoping to expel whatever was caught there as my rippling stomach pumped in involuntary pulses. Soon it was in my mouth. It was salty. Slimy. Spiny.
I watched in horror as a green serpent fell onto the boat from my mouth, covered in blood and green goo. It wriggled and writhed over the deck, inciting more gags. Something else wriggled in my stomach, and I saw something move under the skin of my thigh. That’s when I noticed another barnacle on my shoulder. And my ribs.
More pain erupted from my back as my skin rippled. I felt it in my face. And my throat. Arms. Stomach. Legs.
It wasn’t long before I started gagging again, another creature crawling up my oesophagus and into my throat. I cried in agony as I felt my insides rupture, re-arrange, and ripple. The gagging grew worse as it got to my throat. I cried out with pained exhaustion when I finally spat it out.
My stomach rumbled and twisted, and again, I screamed. Then there was another wriggling up my chest. More gags and hurling. The ripples grew worse as I vomited and spat one wiggling serpent after the other, each accompanied by blood vomit and unrelenting agony, twisting my insides and rearranging them, tearing and gnashing.
The pain was too much. My energy withered, and I collapsed onto the deck, my body convulsing in sync with the wiggling serpents inside me as they tore their way out through my gaping mouth. The sky clear morning sky above me whirled in sync with the boat underneath me, and a part of me knew it was the N’Gahari beneath the surface, sinking the boat to claim their prize.
Darkness lulled me to the other side as my life force crawled out of me, and I welcomed death with open arms.
Sea monster legends aren’t just campfire tales—they’re warnings. And sometimes, the diver doesn’t die. Sometimes, they return… hollowed. If this creature feature horror story of cryptid horror and underwater nightmares resonated with your love of psychological suspense and aquatic folklore, you’ll find more bone-chilling reads across my catalog of horror shorts.
Explore more dark fiction on my BookBub, Goodreads, and Amazon Author pages. Every story, from creature feature horror to body horror and supernatural dread, is crafted to leave you unsettled—and wanting more.
