No sooner has John left him than the train begins to slow for the next stop. Suddenly, Sherlock can picture it all with frightening clarity.
John's gone after their assailant but the car is packed and even if John is starting to lose his grip, he still probably knows better than to tackle an unarmed female in a closed environment and try and take her perfume, dozens of people would stop him and his story would sound crazed, but she knows she's been spotted, she'll get off and try to lose him, John will follow, has to follow, if he has any hope of getting her where he can get the substance off of her and get away with it, if Sherlock doesn't move now he'll be left behind...
He suppresses the urge to shout John's name. He can't risk distracting him or tipping off the woman even more. When they stop he listens for the doors and tries to move towards them in the press of the crowd but he's not fast enough, not without making a fuss. They close when he is still several metres away.
Sherlock's now alone on the tube and not at all sure where he is.
He should have been paying attention, he was paying attention, just not to the stops, he was observing the people, he should have been doing both, why was it so hard to do both, how many stops had it been, it was five stops to Baker Street from Bart's, it had been more than one surely, but had this last been number three or four, it wouldn't have been five, John would have said, wouldn't he, but he was distracted too, Sherlock'll never get home if he gets off at the wrong place...
It's infuriating that something so simple has become such a massive problem for him. Just when he was starting to feel like he had some control, John steps away and he's instantly helpless again. He could use the voice command on his phone to call Gordon or Mrs. Hudson and shout into it for help hoping it had connected and they can figure out where he is, but it wouldn't be exactly be inconspicuous and would definitely be utterly humiliating if not downright dangerous to expose himself that way.
He doesn't have time to deliberate any longer. He has to make a decision. Three stops, he decides. They must have gone three stops, then the fourth was where John and the attacker got out. Baker Street must be the next stop.
Sherlock has to trust that his unconscious mind has put this together for him correctly, that it's not just a shot in the dark. He maneuvers himself closer to the doors so he won't miss his chance again and braces himself for the stop. When he feels the jolt, he steps forward with the crowd, letting them carry him along.
Mind the gap, mind himself, mustn't appear to fumble or flail, head down, shuffle along like one of the herd, he can blend in when he needs to, be surprisingly unnoticeable for a man of his height, if he stays with largest group he should be all right, he's taken this route a thousand times before, sometimes without thinking about it at all, he'll be working on a case and find himself at his own door with no memory of the way home, this should be easy...
There are three exits to the station, Sherlock remembers, and he wants the main one, the one that comes out on Marylebone Road. It's straight up the stairs and out, isn't it? Or is is a left? Why can't he remember? This certainly smells like the right station, that's hopeful. Sherlock decides to stick with the greatest mass of people, the correct exit for him would be the most popular. He keeps in the densest portion of the crowd, going up and notices that his hands are shaking and that his heart is pounding.
It's just the stress of the situation, he tells himself. But he knows it's not. It's the drug working on him, working whatever terrible havoc it's got for him this time. He's got to get home before it sets in. Last time he'd had twelve hours, but maybe he's been dosed so heavily, so many times, that no longer applies.
It's just a hallucination, all of it, the fear, the blindness, the deafness, if he can just focus he can overcome it, there are sights and sounds and people all around him, his eyes see it, his ears hear it, his brain just doesn't know, concentrate, pull back the the darkness, glimpse the world again...
It works, just the tiniest bit. If he pours every last ounce of his focus into his eyes he can make himself see something. Flashes. The edge of a coat, a beam of light, a railing, a pillar, a neon sign. A mosaic of random impressions for just a few fleeting seconds, it's such a relief but it takes everything he's got and it hurts inside his mind and-
Boom. He trips on the rim of a step and would have hit the concrete were it not so crowded, instead careening into several people and taking out several more with pinwheeling arms trying to keep himself on balance. He can imagine the outraged exclamations around him and murmurs appropriate regrets as he steadies himself, once again in total darkness and out of the flow of traffic. He stops and tries get his bearings, trying to pick up the vibrations again to determine the direction of the majority. Suddenly a hand grabs his elbow forcefully and turns him about a quarter turn and gives him a little shove.
Before he can collect any data, the individual is gone and Sherlock is smacking into a set of doors. Relieved, without too much time to wonder about his benefactor, he pushes through and emerges in the less-than-fresh air of a London weekday morning. He walks just far enough out to avoid being slammed into by others coming through the doors and stops, lifting his head and inhaling deeply.
Smell of the busy road, the warmth of the underground from grates below, the awful falafel cart on the corner, sun slanting against him weakly from the left, steady vibrations of the buses that stop here, directly in front of him, less traffic to the right, he's made it, Baker Street is only steps beside him, cross it, another right, 449 ft down the sidewalk, 136 of his strides, give or take, then he'll be home, and John will be there too, he has to believe that, and he'll find a cure for them both before whatever's going to happen next is permitted to do...
He falls in with people again, cautiously, to navigate to the corner and cross Baker Street. But once the light changes and he feels the people around him step forward he can't take it any more. He breaks into a run, gambling that the traffic will obey the signs, heedless of obstacles and pedestrians. He makes the turn and speeds up to a dead run. Most people will be coming the opposite direction this time of day and they'll just have to get out of the way. Miraculously, he mows no one down before skidding to a stop the second he whiffs the greasy bacon and burnt coffee smell of Speedy's emanating from the buildings to his left.
Sherlock scales the steps, fumbles for his key, and is up the hall stairs like a shot, all but tumbling into the safety of the flat. "John! John!" he yells, bursting through the door and scanning with useless eyes. No flash of light. No John.
What if John doesn't come back, what if he's been captured, or worse, and Sherlock is left here alone, waiting, until the inevitable, until he loses something else, or maybe everything else, is that the end game, to kill him, or just to humiliate him to the point where he does it himself, well, he'd already gotten to that point and he's not going back there, so anyone who wants to finish the job will have to come find him, but he'd rather John found him first...
He sits on the rug in the middle of the room, panting, and tries to pull himself together. His heart is beating so fast. It is just adrenaline and exertion, or something else? No telling what the next effect will be. But he has time, he tells himself. He should have time. He quietens his breathing and slows his heart as much as possible. If John isn't back in one hour, he decides, he'll call Grant and set the police looking. But he senses that would be something of a nuclear option with whoever they are dealing with, so best not until it's clear John's not going to make it on his own.
Sherlock closes his eyes and draws up the image of their flat in his mind palace, as he had last seen it the morning they'd set out after the cat burglar. He waits until he has every detail in place, every discarded book and tea mug and coat on the coat rack and then very slowly opens his eyes, willing himself to see it, willing it to be there.
And it's there, faintly, but it's there in its totality, and not just a protection from the way he remembers it, he's seeing it as it is now, cattle skull leaning against the wall needing to be remounted, lamp gone, clothes and dishes everywhere, more of mess even than usual, he's penetrating the fog of the nil, the anti-hallucination, just for a moment, now it's flickering, and he's got to try and hold it but...
"Gah!" he cries aloud before he can stop it, suddenly feeling like a railroad spike has just been driven through his skull. He grabs his head, curling in on himself and squeezing his eyes shut as if that will shut out the pain. It ebbs away, not nearly fast enough, and he straightens back up, gasping for air again. Better save that for a last resort, then, lest he give himself an aneurysm.
He rubs his temples and then taps his fingers on the floor nervously, waiting, wishing he could do something, anything. The minutes drag on and he's just about to make the call when he hears the door downstairs crash open. Sherlock jumps to his feet just in time for John to blow into the room like a solar storm.
John's bright, too bright, crackling with live current, pupils dilated, aura arcing out of control, shading into colors so high in the spectrum even Sherlock can't make them out, energy flying everywhere, he almost wants to duck to avoid it as it lashes toward him, and it feels different, it's not just sight but feeling and sound like he's standing in the middle of a thunderstorm made entirely of lightning...
"Sherlock," John gasps, gulping for air. He's so clearly outlined now, more clearly than in real life, that Sherlock can read his glowing lips.
"Did you get it?" Sherlock demands, watching him through narrowed eyes, trying to assess too much data with too few functional senses. John looks like he's developing a black eye, there are some cuts on his face and knuckles, but nothing seems serious and John doesn't seem to have realized he has them.
John nods not even noticing that Sherlock doesn't need Morse anymore, and tosses him a small glass vial with an old-fashioned aerosol pump. His eyes are darting back and forth, not scanning like Sherlock's do, but orbiting madly, as if seeing too many things at once. Likewise his whole body is tense, twitching, jumping wildly on a small scale. He's trying to keep himself in check, but it's not going well, Sherlock decides.
"The Hound drug?"
"Upstairs. Lab freezer with padlock."
Sherlock nods curtly. He takes a step towards John, almost flinching at the charge and heat that surround them both, and wonders if this part of what the drug is doing to him now. He puts his hands on John's shoulders and they tingle.
"John, it's not real, remember? It's like before. It's the drug. You're hallucinating."
John breathes in very quickly through his nose several times. "The sounds..." he manages. Sherlock can't see any colors other than John's angry aura, but he'll bet his friend is white as a sheet and his skin is obviously clammy.
"What sounds?"
"War. The battle. It's outside. Sherlock, they're coming..."
The war, of course it would be the war, in the absence of any other input or threat John always goes back there, he's never really left, it's a powerful memory, a fear he's never truly recovered from, impossible to counteract, Sherlock can only hope to distract...
"No," Sherlock tells him firmly. "No one is coming. You have to focus. We are in Baker Street. We have been drugged. I need to you help me make an antidote. Listen to my voice, John. Am I telling you the truth?"
John nods, a little uncertainly.
"Good." Sherlock has to stop then for a moment. His own brain is starting to feel fuzzy. Maybe it's because he's been on overdrive for so long, or maybe this is the beginning of the next effect of the drug on him. Or maybe he's just being paranoid. He continues, with effort. "And am I real?"
John nods again, licking his lips and looking around before answering. "Yes. Yes, you're real."
"And so are you. You're John Watson."
"And you're Sherlock Holmes," John replies. Sherlock is so very glad John's said that because it felt like he might have been starting to forget.
He's Sherlock Holmes, that's the one thing he can't ever forget again, and he and John have to make a cure, those are the the only things that matter, identity and chemistry, everything else can be taken, as long as he has those two things he can get the rest back, he'll recite the periodic table on a loop if he has to, run combustion experiments in his mind's eye, repeat his name over and over, anything thing not to lose those two most precious bits of knowledge...
"We haven't any time," Sherlock says, trying not to let urgency shade to panic. That's the last thing John needs to hear in him. "I need you to block it out. It's all a hallucination. I need you to block it out, Dr. Watson!"
"Okay," says John, making a visible effort to pull himself together. He cycles through colors like a nervous chameleon. "Just tell me what you need."
Sherlock follows John's up the otherwise dark stairway to the lab. He hasn't tried to see anything else again, and for now the wattage John is putting out is enough. John retrieves the drug from the freezer and sets it on the lab bench along with the reports from the hospital and the fake perfume vial.
"I need you to read me the report from Caroline," Sherlock orders. "Don't think about anything else, just read me the words on the page." Focusing enough to see the papers and read the words might just tear his brain apart, but he can watch John's lips without pain.
John does as he is told, though his words are fumbling and he cringes at sporadic intervals as though a bomb has just gone off. He's dripping with sweat now. Sherlock gives his mouth rapt attention, afraid he'll misread something but knowing John is in no condition to code and read at the same time right now.
"Wait, wait," Sherlock cries. "What was that? Go back! Maya something?"
John slows. "...interference or obstruction of the the myelin sheathing on the primary temporal lobe neurons and adjacent..."
"Myelin! What's that? I know that word."
Why can't he remember, it has to do with the brain, obviously, he's no neuroscientist but he's studied more than his share of brains, but right now he can't remember a thing about any of them, why had he even bothered, they were just squishy grey matter, the people in them long gone, it had seemed so important at the time...
There are gaps in his knowledge, Sherlock realises. And they're getting bigger. But before he has a chance to let that thought sink in and truly unnerve him, John leaps out of his stool, landing in a half crouch facing the door and brandishing the stool as a defensive weapon.
"John," Sherlock says in what he hopes is a calming tone, for both their sakes. "What are you doing?"
"They're in the house, Sherlock," John says. "My God, I don't have my gun. Okay, you go out the window, I'll hold them off!"
"John, there's no one. Try to remember."
Sherlock tries to remember too, there is no one, of course, it's all in John's head, but there's something wrong with Sherlock's head too, what if he's the one who's imagining it, functionally deaf and blind, unable to detect the advancing army, the warzone outside, wouldn't John know better than him if they were under attack...
No, that's wrong. There's no war. John is being influenced by the drug. Sherlock concentrates with difficulty. "You were explaining to me about myelin."
John shakes his head, wide eyed. "No, they're almost here. Please. Please Sherlock, run!"
He almost does it, it would be easy to slip into that world, easier than formulating a counter measure to a drug he doesn't understand with a mind that's betraying him by the moment, running is simple, fight or flight, but no, wait, that's not what they need here, the harder way is the true one, it always is...
"Soldier!" Sherlock bellows. "Sit down at once!"
John freezes for a long moment and then to Sherlock's great relief replaces the stool and sits back down, though he's still casting worried glances at the door.
"Ignore everything outside. Ignore everything but what I tell you to do and we will survive this," Sherlock says with more surety than he feels. "Now, what is a myelin sheath?"
John calms visibly as he accesses his medical memory. If Sherlock can just keep him working John might be able to avoid another break entirely.
But will he be able to avoid one himself...
"Myelin is like an insulator for your brain," John tells him, tugging at his hair and ears repetitively and cracking his neck like a tic. "It forms around your neurons, it protects them and keeps everything from going haywire. Without it..."
"Very bad things," Sherlock finishes and John nods, digging his nails into his palm. "If something were to interfere with the myelin, would that be enough to cause the problems we've been seeing?"
"Yes. No. Maybe? I can't be sure..." John's fear is palpable and it's starting to get to Sherlock. He can't fight fear and loss of brainpower at the same time.
The knowledge is in there, nothing can take it away, it can only be blocked not erased, not really, even if he tells himself otherwise, he has to trust his mind, he's spent 36 years putting the data in, it knows the answer even if he doesn't...
"The mercury," Sherlock says slowly, the word feeling alien and thick on his tongue. "It's in the adjuvant but not the Hound drug. It reacts with the... the... things.. organophosphates... in the drug and precipitates out to create a... coating. What's it called? Conductive film, a build-up on the myelin sheaths that impairs or disables their ability to function. It makes the effect of the drug unpredictable... and lasting. Everything goes..."
"Haywire," John finishes, his eyes glassy and terror-filled.
Sherlock's not even sure he's understood what he's just told John, but he knows it's right, somehow. He nods.
"So, that means for me, now..."
Sherlock hesitates, partly out of reluctance to tell him and partly from the sheer inability to locate the words. Finally they tumble out without consulting his consciousness. "If we don't find a way to dissolve the coating you will remain in your... paranoid hallucinatory state until your body is unable to sustain it and you will..."
"Die of fear."
"Essentially."
But John mustn't die, Sherlock won't let that happen, he's got to get them through this, he's got to work harder and harder until the answer comes, he's not sure what would be worse, to live without his knowledge or without John or perhaps without even knowledge of John...
"And you?"
His head is pounding now, the headache having crept up on him as his memory crept away. "I don't know. It's working slower on me but thinking is becoming difficult and I am feeling... some sense of irrational fear as well."
"I'm not sure it's irrational," John says, his face grim. "Okay. Let's work, before it gets worse. I'll be your hands, you be my mind."
Sherlock pushes through the fog to the lab in his mind palace and finds it mostly clear and workable. He moves quickly inside of it, breaking down every chemical from both compounds, reassembling them, reacting them with other chemicals until something starts to happen.
He's in the lab, the lab in his mind, the lab in his home, he's with John Watson, and he's Sherlock Holmes, has there ever been anything other than this, has he ever existed outside this place, outside of numbers and formulae and acids and ions, he can't remember, he has to find a cure to something, he has to nullify the drugs, but he can't remember why that is, what came before this or what might happen after...
"Alcohol" he tells John, with difficulty, not at all sure the word is the right one. "Start with alcohol."
John follows his instructions to the letter, despite the fact that his whole body is shaking. His hands are shaking too, but not so badly he can't use them. They always were the steadiest part of him in a crisis. John works and Sherlock talks, knowing his voice might be the only thing keeping John from disintegrating entirely.
Keeping Sherlock from disintegrating entirely, his voice might as well be coming from another place entirely, a distant entity telling them both what to do, like an echo of himself when he was whole, coming from deep inside, from a place the drugs can't touch...
"Add the ionized bromine in equal parts with the solvent," Sherlock tells John watching him and realising he wouldn't even know if John was doing it wrong. "Now, heat it to 435 degrees Celsius for fifteen seconds and then supercool it immediately with liquid nitrogen. If I'm right... we're right, this should simultaneously neutralize the remaining drug in our systems and dissolve the coating that's interfering with the neuron function."
Did that even mean anything, was he making all of this up, just how impaired is his mind right now, for all he knows they might have just synthesized the most potent of poisons or a psychoactive drug or a new recipe for candyfloss, how can he trust either of them in this state, but there's no one else to trust and it's too late to do anything but go forward so he feigns the confidence, the knowledge that has always come so easily to him...
"And then we'll have free-floating mercury in our systems. Great," John says, and his sarcasm is oddly comforting. Even paranoid and crazy, he's got a sharp tongue.
Mercury, is that a bad one?
"The mercury ions will be coated by... stuff... as they are removed and pass harmlessly from our bodies," Sherlock finds himself saying. Then he adds, "I hope."
The cooling tank beeps before John can give him a horrified look.
"It's done." Sherlock says, not at all sure that it is. But it had better be because even the memory of the knowledge is fading, he wouldn't know mercury from what's-it-called if they both him in the face. "Now, to test it."
"Test it? You mean on us?"
"I don't see an alternative."
That doesn't mean there isn't one, just that he can't see it, but he can't articulate that to John right now, can't expect John to do the thinking, it's all John can do to keep himself from having an all out nervous breakdown without Sherlock adding to his panic...
John shakes his head as if trying to clear it and failing over and over. "You're right. I can't last at this heightened state much longer. My heart...adrenaline is a poison you know." His breathing is labored, and Sherlock is glad he lacks the resources to consider what might be going on inside of John right now. "If they don't shoot me first, my own body will take me out. Either way, we've only got a few minutes. But you, genius, you didn't think about delivery method did you?"
Sherlock blinks at him. "What?"
John takes out a syringe that is frankly alarming in size. "Well, it needs to be delivered directly to the brain to have enough potency to work. There's not a lot of options." He draws half of their potion into the syringe and stands.
"John, don't be rash. Think this through," Sherlock says, backing away slowly.
"One shot. Directly to the brain. No second chances. Before they come and kill us. Or worse." John tells him. "It's the only way to be sure. Better than being captured. Trust me."
John looks like a wild thing, a drug addict that's just overdosed, a mental patient, still jumping at imaginary noises, starting at shadows that aren't there, expecting the invasion that isn't coming. He's approaching Sherlock like a mad scientist, unstable and desperate but determined.
And Sherlock can't think, there's got to be another way, but he can't think of it, he's not a doctor and his processor is grinding to a halt, and it's John, hallucinating, terrified, crazed, but still John, if there's anything left in the world for him to hang on to, it's John Watson, even half way to insanity he's worth ten men, and he's all Sherlock can see...
Sherlock find himself also shaking and sweating nervously, and he's not sure he can blame it all on the drug. "If you miss..." he says.
"You die."
Sherlock nods, his hands still up to ward off the needle.
"I won't miss," and there's a glint in John's eye and a brief stabilizing of his right hand that says no, he won't miss. "And I won't let them get you."
And Sherlock knows he won't, John will sacrifice himself to imaginary armies, to the hordes of all his nightmares to keep Sherlock safe, over and over again if necessary, and at the end it's the only thing Sherlock knows any more and somehow it's worth all of his lost knowledge, ten times the value of it, and everything inside of him is very, very calm...
Sherlock puts his arms down. This is how it ends, one way or another, his life in John Watson's blazing, shining, electric hands. He doesn't know much right now, but he knows he could hardly want it to be any other way.
"What about you?" Sherlock asks.
"I'm the surgeon, remember? You first." And with one jerky, impossibly fast movement John leaps wide-eyed towards him and grabs the back of his neck with one hand, driving the long, fearsome needle upwards, deep into Sherlock's foramen magnum with the other. Sherlock's world shatters with pain and then, blessedly, melts into darkness.
