"… Of all the souls I have encountered in my travels, his was the most…" Kirk pauses as his voice fails him. The word "human" comes out choked and harsh. They do their best not to react, but a few of the green recruits look distinctly uncomfortable. McCoy doesn't blame them. Somehow, regardless of time, place, or circumstances, funerals are awkward above all else. He'd feel the same if he wasn't too wrapped up in Jim's grief along with his own. He notes that the admiral will need someone to keep a close eye on him for the next couple of – days? weeks? – well, a while at any rate.

Jim vanishes within minutes, hopefully to his quarters to compose himself, but McCoy sticks around. He has good reasons for doing so: there are psych evals to schedule, rotations to discuss, and a tidal wave of paperwork to avoid for a few precious minutes. More than that, he knows he won't be able to focus on all that needs doing if he goes back to his office alone, but he can't quite bring himself to take a few hours when he's so clearly needed. After all, there is some work he can start on here, and the only logical option is to do what he can.

When he catches himself staring with quiet, nameless unease at the airlock, he chalks it up to nerves.

That night, McCoy dreams.

He dreams of darkness, of cold. Of endless expanses of stars. He feels more than sees his own movement in the inky blackness. Occasionally, his sharp eyes detect something in the distance. A distant comet. A fuzzy cloud that will one day coalesce into a star. The flash of a vanishing ship.

Even though he's moving, he feels frozen, numb from the frigid stars and the endless expanse. There is a terrible beauty to it. The ever-expanding envelope of space is also his cell. It means something to him, something horrifying, but he can't quite recall what.

He awakens to the sensation of his entire body shivering. His room is freezing, even though it's set to a comfortable 295 degrees*. The shaking doesn't stop until he's raised it past 300, and something inside him insists that it could go higher without dehydrating him.

He briefly considers that he might be coming down with a fever, but somehow, the theory fails to take hold. It seems natural, comforting.

Normal.

He next opens his eyes at 0400 precisely. He rises gracefully, making it halfway to the mess hall before remembering that he hates getting up early. 'Oh, well. Too late now.' He resolves to grab something hot to drink and spend a couple of hours catching up on reports.

The replicator produces a perfectly normal cup of coffee, almost syrupy with the summer honey and sugar he can never resist adding. It takes him a few minutes to settle down and get his computer to turn on. (The damned thing's been slow for a week, but he's not going to let some ensign take it apart until he's sure he doesn't desperately need it to go back together.) When he remembers the coffee, he mutters a quick prayer that it's still hot before taking a sip.

The sweetness startles him. It takes every ounce of control not to spit it back into the mug, or worse, onto his monitor. He finishes it, not wanting to waste the energy spent in fabricating it, but hating every mouthful. His next cup is strong and black; its sharp bitterness fills him with clarity.

His office is cold, too. 310 degrees makes much more sense.

He joins Jim on the Bridge for Alpha shift. The admiral clearly finds his presence supportive, and his quiet insistence that Spock will never be truly gone wins him a grateful smile. He's glad he came, even if he's struggling not to shiver in his thin Science blues.

As the crew settles back into its working rhythm, he watches Kirk ('bags under eyes, sluggish movement, probably not sleeping') and Chekov ('alert but quiet, no sign of continued parasitic influence'). Eventually, his gaze starts to wander, finally settling on the young man covering the science station ('not much experience, needs to scan for aberrant dust patterns more often'). He considers going over to instruct the lieutenant ('Oduwole') accordingly, but thinks better of it. After all, what does he know about it? He's a doctor, not an astronomer.

It's been a good day. He's raised the temperature in Sickbay to 312, and a surreptitious scan with a medical tricorder has proven that he's not sick. (He's not surprised, but unsure what to make of it.) He had a perfectly filling salad for lunch. Sure, he's been tired all day, but he was up early, and it hasn't stopped him from getting through more paperwork in two hours than he can remember doing in the past two weeks. He even figured out what was wrong with his computer, and fixing it was… surprisingly pleasant.

Why, then, is he so unfocused and irritable?

He feels as though he's forgotten something. Something any child could remember. At the end of his shift, he returns to his quarters to think about it, rubbing his temples with the effort.

As soon as the door closes behind him, it slips into place. 'Tired and irritable… of course!' Chiding himself for his forgetfulness, he sinks into a crossed position on the floor, already beginning to breathe deeply.

It takes three minutes to remember that he a) can't meditate, and b) always hated trying.

The oversight bothers him a little, but it doesn't seem out of the ordinary. It's… expected. And it can change.

He glances out his room's window, and the uneasiness returns.

When he hears that Genesis is now forbidden to them, his stomach drops. He manages to get through the conversation before retreating to his quarters. He needs to think. To do something. To remember. He has forgotten, and the frustration of forgetting threatens to drive him mad.

His days cease to revolve around work. He rushes through it, darting back to his quarters each night to focus. He paces, his heart pounding in his ears. They're leaving. They're all leaving. Monsters, abandoning him. He's illogically angry one minute, frighteningly calm the next. At night, he tosses and turns, and no change in temperature can make him sleep.

There is something wrong here. Something missing. They need to go back and fix it.

There are brief moments wherein he thinks about what he's doing, what he's worrying about, and there's nothing. As if his mind were a puzzle, and he only had half the pieces. He runs every baseline test he can think of on himself, but as soon as he considers anything requiring a second opinion, the thoughts drift away. Soon, even those periods of self-analysis dissipate, and he's left with nothing but the anxiety and the sense that there's something unnatural in his emotions.

He's no longer uneasy. He's nervous, nearly panicky. When it gets to be too much, he rushes to the spaceport for air. Looking out at the stars reorients him, and he remembers…. Remembers that it's not too late.

He aches with loneliness, but it's only then that he believes that hope is not lost.

They're approaching Earth, and he, for one, will be glad to be home. Sure, it'll mainly be home as viewed through a port window, but at least the sky will be blue and the food will be unreplicated.

A less innocent part of him is already drawing up lists of bars. He's resolved to revisit every neon-lit dive he knows and make the acquaintance of a dozen more.

He isn't sure why, but the specifics of what he'll be doing… elude him. His excitement strikes him as strange when he stops to consider it. After all, he hasn't had a drink in a week. (His last was a toast to Spock, from a bottle of his finest Andorian ale split with a near-silent James Kirk.) It isn't as though the alcohol served at a spaceport is any different from that in his desk. He thinks of women, but the thoughts are unspecific, fading after the first playful helloes.

But it will be different there, he believes. Everything will change as soon as he's home.

Strangely, the tightness in his chest has only worsened. His gut tells him that "home" isn't home. Home is far away, and getting farther by the second. He reminds himself that it's normal to feel a little odd, a little alienated even, after time away. It'll go away within a few days.

What he doesn't expect is for it to suddenly get much worse the night before they land.

'It's wrong. It's all wrong. It's almost too late.' He runs from Sickbay to his quarters. They're locked, but it doesn't matter. He can override it. 'I need to think, plan, meditate. Fix this. Fix this!'

Suddenly, there are people outside. Someone's coming in. 'Jim! He can do it. He'll have a plan.'

"Jim… Help me."

Words drift through his mind, but they aren't his words. He's fading, retreating, even as his voice begs Jim to return to Genesis.

The word "Seleya" feels strange in his mouth, but as soon as he says is, he knows it's right. He finally knows what to do.

And then he's gone, unable to think beyond the terror.

He's not sure whose terror it is.

Captain – no, Admiral Kirk won't help him. He dismisses the shock of betrayal by reminding himself that Jim was drawing the apparent logical conclusion from his behavior.

He awakens in Sickbay, but that's no trouble. He waves his staff off with little effort. An hour later, he's making calls, using every ounce of cunning and intuition to find a space flight, a pilot, a plan.

He's lost. He's lost and he needs to get home.

At times, he pauses long enough to ask himself why he doesn't believe he's home. His hands shake, and he desperately wants to rest and clear his head. But every time he tries to take a break, there's pressure. A headache hanging over his head like a threat. He's trapped, and all he can do is get to Genesis.

He hunches over a glass of Altair water, eyes desperate and hungry, as a strange alien approaches. It's Terran autumn, but even with his jacket, he's cold and lightheaded.

"I name not important. You seek I. Message received. Available ship stands by."

The relief is overwhelming, but he remains tense, cautious.

"How much and how soon?"

"How soon is now. How much is where?"

He glances around the bar. No one looking at them – at least, not specifically. Still, no reason to be bold.

"Somewhere in the Mutara sector."

The words "Mutara restricted" make his blood boil. Did the fool think he didn't know that? 'Why else would I be doing it like this? Of all the idiotic, illogical…' He snaps at his new contact, barely managing to remain civil enough to ask about the price. The coward's refusal is unsurprising. Nevertheless, he finds himself shouting, demanding passage to Genesis until he's approached by a security agent, and even then, he's unable to hold his tongue.

It isn't until he's in custody, alone in a cell, that he recovers himself enough to wonder why he did that.

'I must get to Genesis. Why? Because I have to. It's wrong it's allwrong and I need to – where am I I don't think…'

He can't breathe or think or move. There's something wrong 'wrong with Terra wrong with the ship my body' with him. There's something there.

He wants it out. He needs to think 'to plan to go to…' to sleep. It won't stop and his mind is running a mile a minute. 'Illogical as the mind cannot – no. Must – '

He begs the guards 'please stop I can't – I need – I am – can't find – ' for a sleep hypo, but they don't comply. Or perhaps he doesn't say anything. 'All gone all lost please pleasepleasestop hurting – the pressure the pain I – need this. Apologize but…'

He moans, hot one moment and shivering the next. Sometimes, he screams.

'It's so cold and I can't find… Can't… New plan: escape is the only logical option. I will simply subdue – maybe something's going on and I – stop.'

His vision comes in fits and starts; gaps in his memories appear. More missing pieces.

'I need to focus. Get out. Get out of my – out of here. Out! Get to Genesis. Get to Vulcan. Only I can't – stop. You don't understand – I can't find – stop – where is – Genesis where is Vulcan is – McCoy? McCoy? – stop.

'Escape. Genesis. Vulcan. That is all that matters. All else must cease.'

The Lexorin helps, in a manner of speaking. The hobgoblin's still there, but he… coalesces, for want of a better word. He can feel their consciousnesses as separate entities, and while he's all but certain that Spock knows what he's thinking, the opposite isn't true. Even when Spock takes over, there is no hint of emotion other than his. He'd contest the imbalance of it, but he doesn't really want Spock's thoughts. Besides, thoughts of protest and anger tend to blank out, almost before they appear. He sometimes wonders why, but those moments get rarer and rarer. Perhaps Spock's katra is too unstable to handle his resentment. He knows he wants to help Spock, and that's enough for him. It isn't as though it adversely affects him, and he appreciates that Spock's letting him hold the reins 'of my own body why do I need to so grateful I – stop.'

Most of the time, he's in control, at least on the Bridge, where Jim can see. When Spock steps in to scan an asteroid cluster, he sees the shock and conflict in Kirk's eyes and relents. If it makes the captain – admiral – uneasy, then it isn't worth doing. There's no need to worry their CO.

(When Jim asks, he admits that he'd feel safer giving up a kidney, but stops there. He knows not to go further.)

In his quarters, it's another story. He gets the sense that Spock's katra is somehow fragile. 'Never mind that it's controlling and powerful and – stop.' It needs him to relax, to let it take control for long periods. 'It not he Spock would never do – stop.'

During his off hours, he doesn't eat meat. He meditates in his quarters, each meditation somehow leaving the katra stronger and more refreshed, him more… withered, perhaps. (As soon as the thought appears, it vanishes.) He rises each morning at 0400 and turns in at 2100 after a round of chess against the ship's computer. (He'd rather play Kirk, but he somehow knows that his CO would find it… disconcerting.) He slips into the Science labs when no one's looking to tinker.

He's stopped fighting it. Really, he has. He's a doctor, dammit, and he isn't going to let this patient die on him. If all it takes is a little meditation and a few… minor changes, it's really the least he can do. After all, he reasons, Spock's lifestyle is far 'superior' healthier than his own. There's no reason not to indulge it – him.

The sense of helplessness, of frustration, of violation recurs sometimes, but each time it's weaker. He's confident that the unease will vanish soon.

Spock seems to know that when things get dangerous, it's best to have only one of them at the helm, and that it'd better be him. (His gratitude is overwhelming.) As a result, he's able to get onto and off of Genesis with only the faintest Vulcan tickle in the back of his mind. (It grows stronger when he sees Spock's body, but that seems normal enough.)

It isn't until they're safely aboard the ship that until recently threatened to destroy them that Spock's katra reasserts itself. The Vulcan body laid out in the Bird of Prey's sickbay calls him. He looks at it and feels 'hope? Need? Free will I be – ' confusion.

He wants this. He wants Spock back. He wants 'please go' to help. He tells the motionless body that he misses his friend. He means it.

He doesn't say that he misses himself. He doesn't even think it. It would be selfish and illogical.

"With your approval, we shall use all our powers to return to his body that which you now possess," the priestess promises. He doesn't feel like he "possesses" anything. 'More like "possessed…"' Still, it's nice to be back on Vulcan. The weather's perfect.

She's talking again. He strains to pay attention, but Spock's need is distracting him.

"But McCoy…" She pauses, underlining her next words. "You must now be warned! The danger to thyself is as grave as the danger to Spock." (He resists the urge to laugh hysterically. 'You think?') "You must make the choice."

"I choose the danger," he replies, almost without thinking. As soon as he says it, a burden seems to lift. He feels giddy and lightheaded as he turns to mutter to Kirk.

He's not sure whose relief it is.

He can feel the katra taking over as he approaches the dais. It doesn't worry him. He lies still and takes deep breaths, as if preparing to meditate. He can sense the priestess' hand coming closer and closer, finally lightly touching his face, gently sweeping as if to close his eyes. (He closes them, although he's sure it's unnecessary.) She's silent, but her voice echoes in his mind. His minds.

'My mind to your mind… My thoughts to your thoughts…'

She sinks into him, deeper and deeper. He senses her curiosity. She has never been in a human mind before, and she finds it astonishingly logical. There is… confusion. She sees something in him, something she doesn't understand. It doesn't last long. She delves deeper… she understands.

Suddenly, there is anger, white and hot, unlike anything he's ever experienced.

'Po kupi-tu!?'#

He vaguely recalls tales of pre-Surakian Vulcans, of emotions more intense than humans could dream set free.

'Ek'rasahkos ron-tu! Nirsh tobeg.'

He's shocked he didn't notice Spock's intensity – but then, perhaps the Vulcan allowed McCoy's weak human emotions free rein in the hunt for Genesis.

'Chkariya! Tra vesh-be t'r'va'vat.'

All this, however, is secondary, thoughts scurrying at the back of his awareness. He's far more immediately concerned by the high priestess' rage, growing incoherent and wordless in his mind.

It burns him, hotter and brighter, even as he can sense her struggling to repress it. He tries to soothe her, to apologize, but he eventually decides that all he's doing is distracting her.

It takes him longer than he'd like to realize that it's not directed at him. Spock is there, too, after all, and for some reason, she can barely contain her Vulcan fury.

A moment later, it's gone. The fire has vanished, along with something else. He feels… dizzy, lightheaded. As though he's suddenly lost a toe and can't quite walk right. The priestess' voice in his mind keeps him grounded. Her Standard, while fair, does not run as quickly as her Vulcan thoughts, making it difficult to follow. Instead, he follows the sense of her words, the reassuring undercurrent of protection.

'I must go. Spock requires my assistance. Rest.'

She's gone, leaving only more lightness. With nothing better to do, he rests.

He awakens long before Spock does, opening his eyes to a cavern lit only by acolytes' candles. He takes a few seconds to let his eyes adjust and look around. A few individuals are gathered around Spock's… slab, he supposes. There are two or three clusters of Vulcans towards the edges of the room. He assumes they're speaking, but between the sharpness of Vulcan ears and the distance, their mutters are too low to be heard. His mind is still too fuzzy for him to recall what the room should look like, but it feels large. It's also unbelievably hot.

Slowly, he sits up, hand pressed hard against his temple. The strange lightness has persisted, and he finds himself trying to think of an explanation. 'Not eating enough? Exhaustion? Natural enough, really, with that damned Vulcan in my head. Wonder he relaxes at all. Probably not enough to upset my balance.'

It's only as he swings his legs around to get down that he's noticed. One of the Vulcans by Spock calls, and a shadowy figure detaches from a group near the door. It whispers something as it approaches, but he can't hear. Realizing its mistake, it hesitantly draws near enough to be clearly identifiable as male. 'Why is he so – oh, right. Afraid I'll hug 'im or something.'

"McCoy?" the unknown Vulcan whispers, just loud enough for him to hear. (Nevertheless, the nearest Vulcans glance at them quizzically.) "I am Ketick. What is your condition?"

"Fine, I'm fine," he replies, much too loudly. The sound echoes in the stone temple. "Jus' a bit off-kilter's all."

"… Very well. Priestess T'pliso wishes a word. Can you stand?"

"Dunno yet." He kicks experimentally. "Hang on a moment." After a few more careful movements have assured him that his muscles will obey him, he drops to the floor. Ketick's still watching him, expression dark and intense enough to make him vaguely nervous. He shrugs the feeling off and follows the Vulcan across the room.

"Priestess, I have brought the doctor," Ketick volunteers. 'Was that really necessary? Illogical.'

"Very well. Rihamau solektra-hutaya-besan." The words tickle something at the back of McCoy's mind, as if he should know what they mean. (But, then again, even in toneless Vulcan, it's a pretty clear dismissal.) Ketick salutes them both, turns, and leaves.

"Doctor, we must have words." Her words are so calm, thoughtlessly commanding, that he doesn't think to question her.

They retreat to what at first appears to be an alcove, but opens into a larger room. 'Necessary to go this – oh, right. Vulcan ears.' She doesn't stop until they're well out of sight of the twin dais and the Vulcan swarms. When she does, he nearly runs into her. She turns abruptly, expression – well, expressionless. 'Damned Vulcans.'

"McCoy… how well do you remember the period during which you carried Spock's katra?"

He shrugs. "Well enough, I suppose. Why do you ask?"

"Did anything during that period seem… unusual to you?" There's a hesitation in the question, almost a nervousness. Of course, that's ridiculous. Vulcans may feel nervous, but they'd never be so uncontrolled as to express it.

"Well, I was cold as all get out half the time and stopped drinking, if that's what you mean." Apparently it isn't, because she simply stares at him for a few seconds before continuing.

"What of your… mental status? Did you notice any changes in your thoughts or temperament?"

"Well, sure. I had to, you know, protect him. Let him meditate and control things for a little while every day. If I hadn't, he'd have just… dissipated. Gone away. And this whole mess would've been for nothing."

Something strange flickers in her eyes. "And how were you informed of this eventuality?"

"Well, I wasn't. Not really." He's about to continue, to explain that it was obvious from the start, but he stops himself. It wasn't obvious from the start. He just decided that it was the case. Why did he assume that Spock needed control? Why did he stop worrying that he was – that there was something going on? "I worried about it for a while," he muses aloud. "But the feeling just sort of… went away." He shrugs again, helplessly. "I don't really know where I got the idea."

"I can see that." It's a snappish, condescending sentence, but as someone who's been snapped at and condescended to by Vulcans before, he can't really hear either emotion in it. It sounds almost hollow. "However, you are in control now, are you not?"

"Sure am." He grins, allowing himself to relax on familiar conversational ground. "Back in one piece."

With sunrise comes his reunion with the rest of the Enterprise's crew. He briefly wonders what will become of them after this stunt, but deliberately sets the thought aside. After all, Spock's back. Sure, he barely remembers Jim's name, much less anybody else's, but it's a relief to have him here. ('Not just here. Out there,' some part of him thinks. He ignores it.) They leave Mount Seleya together, a team as they haven't been in far too long.

He finds himself surreptitiously looking over his shoulder at Spock, still with the Vulcans who performed the ritual. The newly risen Science Officer is clearly disoriented, but that isn't what draws McCoy's attention. It's something else, dark and brooding. ('Threatening.')

He shakes the thought loose. Whatever unease he's experiencing will fade, and more importantly, Spock is back. They've succeeded in their mission.

That is all that matters.

* Degrees Kelvin. (I know they used Fahrenheit in canon, but it always struck me as ridiculous given the international cooperation emphasis of both TOS and TNG.)

# I can't speak Vulcan. I looked up the words online, but I know nothing about sentence structure. I welcome any corrections.