This wouldn’t normally have been a job for the fleet’s flagship. The Enterprise was the Federation’s queen on the chessboard, meant for existential threats on a galactic scale, delicate diplomacy, the prevention of war. They weren’t meant for --

“Damnit Jim,” Bones grumbled. “I’m a doctor, not a monster hunter.”

Jim finished fastening his wetsuit around the back of his neck, taking a look at the rest of their away team to ensure they were ready, too. It was just four of them. Jim, Bones, a xenobiologist called Commander Kaltra, and Jim’s first officer, Commander Sulu. All were outfitted for their oncoming dive with wetsuits and life support belts, all standing on the otherwise abandoned sandy shores of a dark ocean roiling with waves. Even in broad daylight, it looked as though the water were a black hole, ready to swallow the sun.

“Today, we’re all monster hunters,” Jim said with a smile. “The Tamakens deserve to live in safety, don’t they?” Bones gave him a withering stare, but not because he disagreed. No, it was because even in the best of times Jim couldn’t get Bones to go to the beach with him for shore leave. Going diving for monsters? That was about the last thing on Leonard McCoy’s bucket list.

But he would do it. They all would. And they needed a doctor in case the worst should happen. Jim doubted the worst would happen.

“You know I won’t argue that, Jim,” Bones finally said with a long-suffering sigh, clipping his life support belt around his waist. The belt emitted a translucent forcefield that shimmered blue over Bones’ face like a diving helmet, then disappeared. They would need these belts to survive in the mysterious waters of this planet. It was a decidedly irregular situation, after all.

Tamaken was home to a peaceful race of land-bound humanoids who had been rather quiet members of the federation for a few decades now. This was the first time they sent a request to the Federation for help. And since the Enterprise was in the area, Jim was more than happy to offer their services. Yes, even just to investigate the case of a few capsized boats.

The thing was, 92 percent of Tamaken’s surface was covered in water, a deep murky green swimming with metals and ores and elements that neither the Tamakens’ nor the Federation’s scanners were ever able to penetrate. Therefore, no one knew what was out there, lurking in the deep. While the phenomenon had been logged for future study, it hadn't been a problem until recently. Now, the Tamakens were certain there was some beast in the water awaiting its chance to drown anyone who might fall overboard.

No casualties were reported from any of the five incidents of capsized boats (nor had anyone reported seeing the creature) but the Tamakens didn’t want to take chances. Jim hoped they could find this beast, maybe relocate it elsewhere in the planet’s abundant waters after a short period of study.

“Are we all ready?” Jim asked, meeting each of his crew members’ eyes to confirm.

“Ready, Captain,” Sulu said with a steely nod, the light of adventure in his eyes. Beside him, Kaltra looked ready to burst with excitement, hopping from foot to foot. Bones just crossed his arms over his chest, grumpy but willing at least to go with them.

“Remember,” Jim said, “if we get separated, rise to the surface so the Enterprise can pick up your signal. If you see the creature, activate your beacons immediately.”

He patted the cylindrical beacon affixed to his hip, and his team nodded. Without further instructions, Jim checked the fit of his life support belt, took a deep breath of the environmentally controlled air within the forcefield, and -- motioning for the team to follow -- he walked forward into the water.

----

Even with their headlamps’ white beams shivering before them, and the muted sunlight filtering through the water, it was difficult to see very far. Jim looked over his shoulder at his crew every few seconds, only their outlines visible in the depth between thick leaves of kelp. They had found the underwater forest far from the shore, around where the Tamakens reported their capsized boats.

There was a high chance the creature was in this kelp somewhere, so they took it slow at first. They wouldn't see it until they were right on top of it, and then they would have to think quickly.

The leaves grew thicker the further they swam. What began as poor visibility became impenetrable visibility, and Jim couldn’t help the feeling of dread sinking into his stomach. Shoving heavy, waterlogged leaves out of the way, struggling to propel himself forward, Jim was focused on his task for a moment too long, it seemed.

The next time he looked over his shoulder, his away team was gone -- disappeared somewhere in the brine. He let out a huff of a breath, bubbles billowing from within the forcefield and dancing to the surface of the water. Briefly, he kicked his way over to the clumps of kelp where he had last seen the beam of someone’s headlamp, but the light was gone.

It wouldn’t do to spend too much time looking, he attempted to convince himself. His own instructions were to rise to the surface and get in touch with the Enterprise if he got lost or separated. Yes, it would be a little humbling for Captain Kirk to be the first to lose his way on a routine scouting mission (even underwater), but he had to at least follow his own rules, right?

Of course, he allowed himself some captainly leeway as he began swimming through the kelp, peeking between leaves in hopes of spotting the flash of a light or the bubbles of someone’s breath.

And, after a moment, there was a flash.

Jim blinked, squinted, paddled in place. That flash did not look like a headlamp, and less so when it appeared again. His eyes traced the swift and glimmering movement of light, tinged green so bright it was nearly white. It flickered in a curved line upward, then back down. As Jim watched, another streak of light joined the first, shining parallel to its fellow.

Wracking his brain for answers, he could only imagine that the lights were a kind of bioluminescence, but whether it was coming from a plant or a creature, Jim couldn’t be sure. Cautiously, he clicked off his headlamp, and began a slow and agonizing swim toward the light. If this were the beast they were looking for, the movement of the kelp parting around Jim’s body would no doubt alert it to his presence. Yet the lights didn’t move except to continue to flicker and flash.

Keeping low to the ocean floor, Jim got just close enough to peek up through the kelp toward a patch of water-dimmed sunlight, his heart hammering when he set eyes on the last thing he was expecting, suddenly illuminated by even more streaks of bioluminescence.

It was the creature. Or, rather, it was a creature.

Jim’s eyes rose up its length, beholding a billowing tail like that of a fish, long and slender with gossamer fins that swayed in the water, like the kelp swayed around them. That tail was the source of the bioluminescence, streaks of light illuminating the curve of the creature's pelvis and fins, and shining from the scales on its webbed hands.

But from the waist-up -- by the stars, it was humanoid. Deep green scales ascended its taut abdomen, growing sparse along its waist. It boasted strong arms and shoulders, and a look of such intensity on its face that Jim forgot about the beacon at his hip, the landing party he’d lost, the ship to which he was supposed to return.

Because Jim’s eyes met the piercing, glowing green of a predator’s eyes, set deep into a handsomely chiseled face, wreathed by dark, flowing hair that swayed in an impressive arc around its head. And his heart jumped in his chest. That face was impassive, but its eyes said everything the creature could not.

It had seen Jim.

The lights along its tail grew brighter, flashing quickly, fins spreading to show off their glow while the creature’s tail whipped through the water in warning. Its eyes narrowed under furrowed brows, and it dropped its head as if to charge at Jim.

“Wait!” Jim called, voice muffled through the water, though it rang clearly within his life support forcefield. It was possible, given its appearance, that this creature could speak. Could listen. Could be convinced not to tear Jim to shreds.

But in the blink of an eye, the creature slid through the water like a torpedo, bubbles rising in its wake, tail flashing, arms reaching forward.

Jim tried to paddle backwards, fumbling for the beacon at his belt, but the creature grabbed his wrists with such strength its claws nearly broke the skin through his wetsuit.

Gasping with sudden pain, Jim tried to struggle from the creature’s grip as it pulled him forward, its tail curling behind him to keep Jim from swimming backwards. The tail’s caudal fin fanned out around them, and the creature opened its mouth to reveal a row of sharp teeth, deadly as a piranha’s but large enough to kill Jim nearly instantly.

He closed his eyes, teeth clenched, and the creature’s face approached the vulnerable skin of his neck -- a stretch just below the line of his forcefield, yet peeking over the collar of his wetsuit. Those teeth would hit an artery, and it would be over. He’d be torn apart. He had to struggle, to fight, to --

Something wet, slimy, and cold brushed against his skin, and Jim’s eyes shot open immediately. Though the creature’s hair was billowing around it in a screen of black, he could still see where it was practically nuzzling into his neck, its tongue lapping at his skin while its lips grazed his pulsepoint.

It pulled him closer by the wrists, its prehensile tail now curling possessively around Jim’s ankles.

Fear and adrenaline caused his body to jerk in the creature’s hold, and it lifted its head to meet his eyes.

Shifting both of Jim’s wrists into one of its webbed hands with swift dexterity, it raised the other to the side of Jim’s face. Jim yanked away, but couldn’t move far as that hand rested on his cheek, causing the forcefield around his head to flicker.

The creature’s lips turned downward, a frown Jim would call petulant if he weren’t facing down the terrifying specter of a watery grave. It scanned him with its eyes, finally settling its intent gaze on the belt around Jim’s waist. Jim shook his head frantically.

“No, I need this to brea --” the word was cut short as a rush of water flooded his mouth, and the belt that had been torn off his waist was discarded to sink to the ocean floor out of sight. Jim redoubled his efforts to break free, but he didn’t have much time to do so. Before he could even think to formulate a plan, the creature’s mouth was on his, breathing air into his lungs. He swallowed it greedily, hands twitching in the creature’s grasp.

Finally, the creature seemed to have reached its goal. It placed its free hand once again against Jim’s now immobile face, and static leapt between their skin, sharp and stinging in the water.

A voice flowed into Jim’s mind like air flowing into his lungs, like the current teased Spock’s hair and fins into swaying, and --

Spock? Jim’s eyes fell closed once again, and he tilted his head so Spock could cradle his face, breathing into him. How did he know Spock’s name?

My mate, a voice whispered in his mind, while the same tongue that had tasted Jim’s throat just moments ago now bullied its way into his mouth. A groan rumbled in Jim’s chest. I have sought you for so long.

The creature, Spock, was speaking to him somehow, even as the exchange of air between them kept their mouths occupied. Jim didn't know on which threat to place his focus; Spock’s thoughts, or his exploring tongue.

But the kiss -- and oh, it was a kiss -- stole his breath and his attention all at once as he leaned into it, and it didn’t feel much like a threat after a moment.

Jim found himself licking between Spock’s lips, his body relaxing in Spock’s hold as pleasure sang through his nerves. Briny water slipped between their lips as they parted and pressed and parted and pressed, but Spock swallowed it all in, and breathed life into Jim’s mouth exactly when he needed to. Jim grew lightheaded, yes, but not from lack of oxygen.

A voice in the back of his mind, far quieter than Spock’s voice, told him to fight Spock off, struggle to the surface, call for help. But Spock released his wrists to bring his hand to the small of Jim’s back, to pull their hips flush together, and Jim’s mind almost went blank.

Calling for help was the last thing on his mind as his eyes screwed themselves shut, lost in the feeling of being consumed. He tangled his hands into Spock’s wild hair to hold him close, cradling the back of his head and caressing the gills behind Spock’s pointed ears. A pleasant shudder traveled through Spock’s body against him.

But he had to communicate, before anything else happened between them, before he let himself get dragged into the depths to his doom like the sailors in old tales who encountered deadly sirens in the sea. He had to figure out how to speak to this creature. This person. His mate? At the thought, an amused hum sounded within his mind, and Jim tried to think again. Louder this time.

Why me? Jim thought, stroking Spock’s cheeks with his thumbs. His skin was cool, human-like but smoother, a contrast to the subtle texture of his scales. A contrast, too, to the points of Spock’s teeth, which grazed against Jim’s tongue, his lips, so close to breaking skin and drawing blood. But the danger of it made Jim’s heart race faster, spurred on by delight rather than fear.

Spock’s voice rumbled in Jim’s skull again, low and gravelly. I felt your mind. As soon as you entered the water, I felt it. I knew.

The hand affixed to the side of Jim’s face clenched its fingers, the bite of nails into Jim’s skin somehow soft and adoring beneath the pain, and Jim melted into the touch, melted against Spock’s body, allowing that tail to slide up his back.

Hips shifted against Jim’s, slow and rhythmic and imminently powerful, and Jim realized only then that he had grown painfully hard under the tight confines of his wetsuit. A little kissing (especially under threat of death) didn’t usually get Jim hot and heavy this quickly, but something was happening in his mind, the exchange of thoughts and words and emotions and sensations occurring without any true intention. The result was arousal -- Spock’s and his own -- bright and warm in Jim’s gut.

Through the brilliance of the mental connection that swept Jim’s fear under the rug of his desperation, Spock shared his memories. It happened in an instant, images and emotions flickering through his mind like the bioluminescent streaks that had drawn him to Spock in the first place.

Jim witnessed, as if experiencing it himself, the gut-sinking shame of knowing Spock could not find a compatible mate among his people, a race of creatures like himself that lived beneath the water; the edict of his leaders to travel though the seas in hopes of finding someone who was suited to his mind, perhaps among the Tamakens; the terror that he would be alone even then, but the desire to know how it felt to find his missing half; the taunting shadows of boats above the surface, where Spock was unable to sense anyone's mind, let alone find a mate among the crew; Spock’s choice to spill each Tamaken into the water so he could feel their minds through the current. None of them produced in Spock the psychic thrum he knew would signal his nearness to his mate. The disappointment each time he capsized a boat, only to swim away and try again -- a ritual he would repeat, maybe forever, until the one destined to be his lover would make their way into his waters.

And then, the moment Jim set foot on the shore, waves lapping at his feet.

I did not simply need a mate, Spock said in Jim’s mind, breaking through the memories like glass shattering. I needed you. Only you.

How? Jim wanted to ask. How could they be destined for each other, when it was mere coincidence that Jim even found himself on this planet at this moment? When they were of two different species, worlds apart?

Spock’s hands ran down Jim’s back, the meld of their minds slipping away like water. The last thing Jim heard, quiet as a whisper at the edges of his consciousness: I don't know how. And I do not care.

Jim found he didn't, either.

Smiling against Spock’s lips, Jim wrapped a leg around Spock’s abdomen, allowing Spock’s hands to wander, to grip Jim’s flank and thigh with a hidden but intoxicating strength. Spock’s tail curled tighter around Jim to keep him close -- though all thoughts of struggling free had long left him by now -- the thickness of it rubbing against Jim’s backside. Jim wished he wasn't wearing a wetsuit, wanted easier access to feel Spock’s scales against his skin, to relish in the weightlessness of the water buoying them, to let Spock use him as his mate.

But there would be time later to explore each other's alien bodies, to learn how to take pleasure from the differences in their anatomy. For now, Jim took his pleasure like an animal in heat, rutting his hips onto the muscled curvature of Spock’s tail, wildly seeking friction. Between their bodies, a slit in Spock’s scales revealed itself and the green tip of a phallus began to poke through.

Delighted, Jim trailed his touch down Spock’s slick scales to find it, teasing its tip as more of it grew outward from its sheathe. Spock growled into his mouth, muffled and wet, and Jim tried not to smile any wider lest he end up with a mouthful of water again. But he could barely help himself as Spock’s cock elongated, revealed itself fully, narrow at the tip and tapered at the base, twitching with interest in Jim’s hand.

Jim was content to hump Spock’s tail while he used his fist to please his lover, while Spock sucked out Jim’s breath and returned it to him between the seal of their lips. But he could tell even without Spock's thoughts in his mind that Spock wanted more. He knocked Jim’s hand away with one of his own, and clenched a fist into the fabric of Jim’s wetsuit, just above his groin.

Jim closed his eyes, let Spock rip a hole into the last line of defence he had against the elements. But the relief of pressure caused him to gasp, water flooding his mouth as he ripped his lips away from Spock’s.

Spock pressed them up against each other, his incredibly strong hand now wrapping around them both, slick and powerful, its scales textured with tiny bumps. They began to rise slowly through the water toward the dappled sunlight above, Jim’s vision going blurry. Spock was licking at his neck again, tearing more holes into Jim’s wetsuit without logic or pattern, frenzied, and seemingly forgetting that his mate needed to breathe.

But it was alright. Jim choked, grabbed onto Spock’s shoulders and squeezed, his grip faltering as his vision blackened and flickered at its edges. Maybe he would die here after all. Maybe Spock would kill him. Maybe all the love and longing he’d seen in his mind was a trick. Maybe Spock wanted to drown him after taking what he wanted. But coherent thought began to fade as Spock’s grip between them tightened, and Jim threw his head back. His eyes opened, sightlessly regarding the light wavering on the surface of the water, growing closer. The last of his air fled his nose and parted lips in faint bubbles that burst over his vision, and Spock sunk his teeth into Jim’s neck.

The pain flashed, the deprivation of oxygen caused his heartbeat to falter, the pace of Spock’s hand increased fast and ruthless, and -- oh.

Jim didn’t realize he was coming until his lips broke the surface of the ocean, until a breath of warm air flew into his lungs, and he cried out into the echoing nothing above him. He jerked and writhed in Spock’s hold, his grip on Spock’s shoulders leaving green imprints in Spock’s skin.

Spock’s true voice was a deep, animal warble as he, too, convulsed in a sudden surge of pleasure, something thick and viscous bursting from him over Jim’s cock and stomach before being swept away by the current.

Jim sucked in frantic breaths, his chest heaving under Spock’s touch as Spock caressed every inch of him with hands and tail. And when his vision finally cleared from the fear of drowning and the power of his climax, he finally saw Spock in the gentle light of day. Not a creature, but a man. A mate. A lover.

His skin, pale and green-tinted, looked as soft as it felt, unblemished and slick. His hair, which had flared and wavered in a dramatic crown in the water, now plastered itself to his head, laying in kelp-like strands over the surface of the still ocean. And when he smiled, subtle and small, the points of his teeth were hidden behind kiss-swollen lips.

Jim couldn’t help it. He laughed, pulling Spock closer to him, running his hand up Spock’s back. He didn’t know if Spock would understand him when he spoke, but he tried all the same.

“I think we have a lot to figure out, you and I,” he said, voice hoarse from choking on seawater, breath warm in the crook of Spock’s neck. “But for now, I need to return to my ship. I’ll come back for you, alright? Can you trust me, Spock?”

Spock pressed a kiss to Jim’s forehead, as if he did indeed understand. And he reluctantly released his hold around Jim’s back.

How Jim could return to his ship with a torn up wetsuit and the graphic report he’d have to make, and still maintain his dignity, he’d have to find out later. For now, he took Spock’s hand, squeezed it, and let it go. A promise.

He didn’t need Spock to touch his mind again to understand what his new lover was feeling. He saw it plainly in his eyes as Spock sank back into the water, casting a knowing look over his shoulder. Spock had been searching for Jim his whole life, and he would wait as long as necessary to ensure they could be together.

And Jim? Jim thought he’d never find what he found here today. And he certainly never thought he’d find it in an alien ocean. A welcome surprise -- for them both.

As Spock sank once more beneath the brackish surface of the water, disappearing into the fields of kelp below, Jim reluctantly pulled his communicator from where it was affixed to his hip, having thankfully survived Spock’s frantic tearing of his wetsuit.

Smiling something dopey and satisfied, he flicked it open. “Kirk to Enterprise,” he said, a little breathless. “Time to beam up the search party. I think our mission has been a success.”

That was an understatement. Or perhaps fully and completely incorrect. It didn’t matter, though. He’d explain it all when he had to. Oh, the look on Bones’ face would be fantastic.