So this story happened because I'd gone to see Star Trek Into Darkness for the fourth time and one of my favorite parts of the movie is when Khan, Kirk and Scottie are infiltrating the mama ship and those two 'private security' guys fling themselves in front of Khan and get a savage ass kicking. And then I thought, man I can totally picture Sherlock having a moment of brain dead rage and becoming brutally lethal...

And thus I give you:

Surprise

When he thought back on it, John realized that in all the time he'd known, lived and worked with the eccentric genius, he'd only ever witnessed it once before.

But even that had been different.

That one time at the pool, John had seen it plainly as it blossomed unimpeded across the detective's face like a flower opening itself to the morning sun; an involuntary and unstoppable action – that was how he'd known it was real – that Sherlock had genuinely been surprised to see him standing there with bombs strapped to his torso.

But still – different. Different because Sherlock had arrived at the pool knowing something was going to happen, he just hadn't known what it was. So yes, he'd been surprised but he'd been expecting it, and that just wasn't the same thing.

This time John had seen the real thing. He'd witnessed an undiluted collision of expectation and reality rip through Holmes' psyche like an electric shock; it hadn't been anything particularly nasty or out of the ordinary, but John supposed it didn't have to be. A shock was a shock and it made your heart jump into your throat and stole the air from your lungs and made your body move well before your brain had time to catch up – a reflex bred into human DNA for millions of years.

The fact that John had experienced this very sensation himself, in degrees dancing on the edge of mild and severe, and witnessed other people struggle through that jolt of intense and sudden awareness, could never have fully prepared him for how Sherlock Holmes had dealt with what should have been, at most, a medium threat catching him off guard.

They'd been carefully stalking a killer into a dilapidated old apartment complex and had only just entered through a side door, obviously intended as a fire exit in the past. Sherlock had been in the lead, with John and Lestrade shoulder to shoulder behind him, guns drawn and thrust before them, and three police officers brought up the rear.

With the first footfalls to touch the floor in years rose a cloud of dust that tickled their nostrils with a stale smell of lifelessness and disuse, immediately setting everyone on edge in the eerie silence of the long dead building, their footsteps crunching loudly on dried leaves and garbage despite all their care to move quietly. The light from the still open doorway clung stubbornly to the walls and dusty air but lost strength with every step they took, giving way to the monstrous shadowy labyrinth that lay before them.

As they were coming up on the first intersection in the hallway, Sherlock slowed to a stop just at the edge of the corners, making a movement that told John he'd likely been about to wave the officers forward because he himself didn't have a gun.

And then it happened.

Sherlock had not predicted an accomplice; nor had there been any evidence to suggest hired help was going to be an issue. The killer had all the habits and characteristics of a narcissistic loaner, so when two men suddenly materialized around each corner, mere inches in front of Sherlock, it had given them all a start.

John had instinctively raised his gun, seeing Lestrade do the same from the corner of his eye, but it was useless with Sherlock standing right in the line of fire. He'd seen their large knives flashing like the teeth of an angry beast in the darkness and then heard a small sound somewhere between a gasp and a snarl pulled from Sherlock's throat before everything churned to a sluggish crawl in John's brain.

He watched the man's wiry muscles harden and pop under the thin material of his shirt. They coiled down the length of his arms and tightened around his bones like a boa constrictor, pulling his arm from it's place by his side and propelling it upwards through the air, gaining speed and strength as it traveled, finally connecting with the face of the man unlucky enough to be closest to him.

The force behind the blow was terrible and ferocious and had the same result as a two by four to the head; a sickening crunch, the faintest sound of blood splatter hitting the wall and the man fell like a sack of potatoes, half his face stained red, and didn't move again.

Before anyone had a chance to react, Sherlock was moving again. Spinning from the first target, his other arm swung out in an arc, a savage cry launching itself desperately from his chest just as his fist plowed into the second man so hard it folded him in two. Knee met skull with another crack and then Sherlock's bloody hand was tangled in his attacker's hair, hauling his face up and driving it forward into the wall with a wet crunch and John saw the spray of blood scatter through the air like water from a shower head.

"Freeze!" Lestrade cried before the corpse had even hit the ground, and for a second John had thought the D.I. was talking to Sherlock, but then he noticed the shadow of a third attacker running down the hall towards Sherlock's back.

The consulting detective was already spinning, a flash of metal in his hand carving a silver gash through the air before it was buried to the hilt in the temple of his third assailant. The blade split the man's skull easily and sunk through his brain like butter.

John didn't know when exactly the consulting detective had stolen the knife from his attacker but didn't have the brain power available to analyze it just then, fully preoccupied with sluggishly processing the fact that he was looking at the unnatural protrusion of a hunting knife jutting from someone's skull. It was like throwing a wrench into the gears of a machine; neurons stopped firing and blood seeped into places it wasn't supposed to be and everything ground to a halt – body going slack, gun tumbling from limp fingers and face frozen in place.

Sherlock released the handle of the knife and watched the man tumble sideways to the floor, silence trickling through the cracks between his ragged breaths like sand. Heavy. Suffocating.

After a moment, when his breathing had evened out, the consulting detective bent down and plucked the gun from the dusty floor deftly and John swallowed when he noticed Lestrade's weapon inch ever so slightly in his flatmate's direction.

"Sherlock?" The D.I. called quietly, trigger finger flexing convulsively.

John glanced around at the other officers, taking in their uncertain expressions and the white knuckled grip on their guns.

"Sherlock, why don't you put the gun down for a minute and catch your breath." Said Lestrade, his voice a bit more forceful but trembling ever so slightly with something John couldn't quite put his finger on. Fear, perhaps, that Sherlock had finally snapped like Donovan had always said?

But when Sherlock turned around, his face was calm as ever and he looked like nothing out of the ordinary had just happened. If it weren't for the three mangled bodies at his feet and the blood dripping from his skin and soaking through his shirt, John would have thought he'd just imagined the six second skirmish.

When Sherlock became aware of the looks he was receiving, he glanced down at the corpses and then back up with a sheepish look.

"They startled me."

It was this innocent admission, and the way Sherlock's eyes and face were unusually open and honest, coupled with the knowledge that the man really didn't seem to realize the significance and severity of what he'd just done that chilled John to the core.

'I'm not a psychopath, I'm a high functioning sociopath...'

Time to contemplate what that revelation meant to him was not a luxury he'd been allowed at the time, as his flatmate had swiftly turned and stalked into the gaping maw of shadows before them, calling for Lestrade and him to follow. After that it was easy to lose themselves in the chase; with the darkness pressing in on them hungrily, hovering around like a vulture waiting for them to fall, they needed to give the situation their full attention and John gladly quieted the rolling waves of unease in his gut to focus on the task at hand. However, when the time came, after they had hunted their killer into a corner, John kept his eyes on Sherlock, half expecting the man to savagely pounce, but he hung back and allowed Lestrade to cuff the criminal and rattle off his rights, apparently quite disinterested in the proceedings and absently trying to wipe the blood off his hands.

When they had escaped the tangle of dark hallways, the harsh light of day burned away the shadowy veil that had been hiding the grisly details from John's keen eyes and he was given the chance to see the result of Sherlock's berserker moment in full force. He swallowed hard as he stared wide-eyed at his friend's profile; blood dripped down his face and coated his hands, making his pale eyes pop dramatically. He felt, for the first time, apprehensive standing beside his flatmate and continued to watch him closely when a medic handed over a damp cloth and he wiped the blood from his face and hands as best he could.

Lestrade hadn't asked them for a statement, merely told them to go home and he'd call them tomorrow, earning a strange look from Sherlock.

With a grateful nod, John had firmly grabbed the taller man by the arm and steered him away from the crime scene before anything else could be said. Throughout their taxi ride home, John felt Sherlock's heavy gaze settle on him six times before they stopped outside 221B. The man was strangely quite and uncharacteristically still after just finishing up with a case and John tried, unsuccessfully, not to think about why.

Had Sherlock's actions finally caught up with his brain? Was he starting to realize what he'd done?

By the time they'd entered the flat, neither of them had yet to say anything and the silence between them was growing oppressive.

"John?"

He froze at the tone of voice and turned to regard the other man, silently taking in the dried blood, stark against his pale skin and making patches and dots of his dark shirt even darker. His icy blue eyes were wider than normal as he stared at John with his hands clenched into tight fists.

"What's wrong?" Sherlock asked quietly.

And John really shouldn't have been surprised that the genius didn't know the answer.

"Sherlock..." He trailed off, shaken by the contrast between the merciless bloodshed he'd witnessed less than two hours ago and the confused, clueless expression he was seeing now.

"Are you upset with me?"

Well there was a good question; one John took a moment to ponder. Was he upset? If yes, what sort of upset? Alarmed? Angry? Did he even have any right to be upset?

He shook his head to clear it. "I...I don't know."

This seemed to annoy the other man. "How can you not know if you're angry with me? Usually it is quite clear. Even to me." He snapped.

"It's just...at the apartments, what you did to those men...it was-" he struggled to find a word to describe it. "-brutal."

"They attacked me." Countered Sherlock, sounding more than a little offended.

"I know, I've just never seen you react that way. You could have easily-" he snapped his jaw shut abruptly. He could have easily done what? Disarmed them? Dodged out of the way? Ducked and let Lestrade and John shoot? Every one of those scenarios had one glaring problem: Sherlock would likely have been hurt. He sighed and pulled a hand through his short hair. "Never mind."

"John, tell me." Sherlock insisted; demanded. His arms were crossed stubbornly over his chest and the look on his face was bordering on angry; if there was one thing Sherlock Holmes hated it was being denied answers.

"There's nothing to tell." John tried to convey the honesty of those words in his tone but, as expected, it was lost on the other man.

"It is obvious that I've done something to-"

"No, Sherlock. I thought you had but I was wrong." John explained calmly, flashes of the fight igniting behind his eyes like a dancing flame, threatening to burn the sincerity from his voice. "I was shocked by what you did to those men...your reaction was so violent." He blinked down at the ground and crossed his arms uncomfortably. "I just wasn't expecting it, is all. I feel a bit shaken."

"I told you, they startled me."

When John looked back up he was met with the familiar cool, calculating gaze.

He frowned. Something was off. Something was different. Sherlock's pale eyes held the weight of something altogether more intense than the calmness he was trying to portray; his body was rigid, muscles taut like a quivering drum, and his hands were shoved deep in pockets. Sherlock had gotten his answer but he wasn't at all happy with it.

"I know." He spoke carefully, feeling his brows knot themselves with the anticipation; of what, he wasn't sure. "And once I took a moment to think about it I realized you probably handled it the best way possible. If you'd have done anything else but take them out like you did, someone likely would have gotten stabbed or shot."

"Exactly what I thought."

"No." He couldn't help it, the word had sprung forth from his lips without his consent and he blinked a bit, eyes wide.

Sherlock's piercing blue eyes stabbed at him like needles. "What?"

Steeling himself, John allowed the soldier in him to straighten his spine and surface just long enough to grant him the courage to speak his mind. "No, you weren't thinking." He cleared his throat, viciously squashing the sick clawing at his stomach trying to tell him that honesty might not be the best course of action at the moment. "There wasn't a thought in your head when those two men jumped around that corner. If you must know, any lingering unease I may have is solely an effect of that realization."

The setting sun was casting beams of red light into their sitting room, cutting bloody shadows into pale swirls of dust. As Sherlock took a step closer to him, a beam fell across his face, carving it in to something sharp and sinister, highlighting the dried blood in his hair and around the edges of his pale face like a morbid blush; the scarlet sunlight filtered through those shocking blue eyes and John found himself swallowing nervously under Sherlock's surreal violet gaze.

"And why," The detective purred dangerously, his voice so low it rumbled from all the way down in his chest, "Would that unnerve you? You, a soldier, who has likely faced similar situations. You, a man trained in combat. You, a man that has killed for lesser reasons than what I did tonight."

John's mouth opened several times but no words came out. He wasn't at all sure where to start after feeling the pain of those well placed blows and a sickening concoction of anger, disbelief and fear was mixing in the pit of his stomach. He was more than a little angry with Sherlock's last comment, knowing full well it was a reference to the cabbie he'd shot for the idiot after all the genius had seeped out his ears and he'd decided to take that damn pill. The disbelief was easily attributed to Sherlock's shameless attack on the credibility of his skills as a soldier and the fear, well, if he was honest, John knew he was, for the first time ever, a little afraid of the look on Sherlock's face.

It took but a second for him to reign it all in and focus.

"You're right." A small, victorious smirk pulled at the corner of Holmes' mouth. "I have faced similar situations, in Afghanistan mostly, and I have been trained for it." He fixed his own stare on the man, knowing he could be intimidating as well if the situation called for it. He dropped his voice an octave and let the anger he felt harden his gaze. "You misunderstand, Sherlock. What alarmed me was not the situation itself, but the loss of control you exhibited. Yes, I've killed, likely more than you have or ever will, but I have never, ever, lost myself like you did."

The taller man's gaze had changed into something ugly.

"And don't you dare pretend it wasn't terrifying for you as well." John watched half in shame and half in triumph as Sherlock blinked, teeth baring for a fraction of a second behind curling lips. "Your head was blank for those six seconds, maybe for the first time in your life, and when it caught up with your body and you looked down you saw three bloody corpses at your feet!" John realized he was nearly shouting and ruthlessly reigned in his emotions. "You think I don't know you well enough to recognize when you're over compensating? The look on your face when you turned around scared the hell out of me, Sherlock. Too calm, your hands were shaking, you couldn't pull enough air into your lungs – I may not be as smart as you but I know panic when I see it."

His words hung in the air between them, floating through the swirls of highlighted dust and John could actually see walls slamming into place around his friend. His eyes went to the floor, his arms crossed over his chest and his body began to shift away before John stepped forward and grabbed his arms.

"Sherlock, it's alright-"

"It's not alright!" The man snarled and he was shoved violently away.

The shadows seemed to be growing, feeding on the dark mood in the space around them and breeding, cutting bigger chunks out of the light and casting a harsher image to the room. John ignored the chilling atmosphere and steadied his breathing as Sherlock glared at him, one half of his face in shadow, the other half illuminated crimson from the sunset searing a path through their window.

"Sherlock, it is alright." He kept his tone soft, like he was speaking to a caged and agitated tiger. "You did what you had to do-"

"I don't lose control!" Sherlock suddenly roared, his voice deep and frightening and so strong it shook the windows.

John swallowed, feeling the hairs on the back of his neck stand on end. Tonight was a first for two things now, this being the first time Sherlock had left his ears ringing from the sheer volume of his voice.

"Sherlock, there is nothing wrong with how you reacted. It's human nature to-"

"Don't! Don't you dare finish that sentence!"

"Alright, stop this! You're not-"

An angry growl told John he might as well save his breath as Sherlock was no longer paying attention to him, but had turned to face the window, his pale skin bathed in the angry red glow of the sunset, highlighting the muscle jumping in his jaw.

"I don't...I don't lose control. My body doesn't do anything I don't tell it to. Nothing."

He looked desperately at the other man, feeling something cold coiling in his stomach. "Sherlock..."

A ragged, angry breath filled the detective's lungs and trembled back out, carrying something akin to fear on it's back.

"I didn't mean to...they startled me. It was so fast..."

His shift from anger to despair was staggering in its speed and John blinked his way through it, cautiously moving back to the younger man's side. "Sherlock, please calm down."

But the detective whirled on him, eyes wild. "You don't understand-"

A loud, resounding CRACK! cut through the silent room like a snapping bone and John felt his hand burn with pins and needles while he watched Sherlock stagger into the desk beside him, a hand to the side of his face, eyes wide as he stared at his flatmate.

"Sherlock, listen to me." John said sternly, ignoring the guilt that writhed in his stomach when Sherlock rubbed at the red spot on his cheek, "I know what happened today was a new experience for you, but you aren't the only person who has been startled into actions your brain didn't agree to." He paused but the other man didn't interrupt, merely stared at him blankly. "What you did was...incredible and terrifying and if you hadn't done it, one of the good guys would have gotten hurt. So your brain took a back seat for six seconds," He shrugged, hoping it looked more genuine than it felt, "Big deal. Sometimes thinking slows you down." He looked down at his hands then, unable to hold the man's gaze as he spoke his next words. "Just because I've never experienced such a feeling myself doesn't mean I don't understand that it's sometimes the only thing that saves lives. I've seen thoughts get in the way of critical decisions before; decisions that the body should have made in a thousandth of a second but couldn't because it was frozen by the mind's fear that maybe the solution would be worse than the problem." He sighed. "Indecision kills people, Sherlock. You did what was needed; nothing more, nothing less."

Again the silence fed on their discomfort, swallowing any stillness of mood and turning the air into a shaking, jittery current of agitation that ate away at John's nerves until he was sure blood would star dribbling out his ears.

"I rather think you are unaware of your own strength, John." Sherlock muttered, pressing his hand to his cheek again.

John's mouth twisted when his guilt came back full force, although he felt better when he realized Sherlock's voice was level and steady and he seemed to be breathing normally again.

"Yeah, well, you wouldn't bloody listen to me. Had to get your attention somehow." He shoved his hands in his pockets and cleared his throat. "Tea, then?"

"Please."

After Sherlock had gone and showered, they spent the rest of the night in tea-sipping silence with the tele on low in the background, shoulder to shoulder on the sofa as they gratefully let their brains latch on to whatever mindless tv show happened to be on. Long after the orange glow from the street lamps outside had flooded their living room and the infomercials had taken over all the channels did John realize it must be getting quite late and he gently took the empty mug from Sherlock's slack fingers and set it on the coffee table.

"Sherlock?" He placed a hand on the man's shoulder, squeezing lightly. "Hey."

In a fluttering of long lashes, pale eyes sleepily peered up at him and he smiled. "Try and get some sleep tonight, yeah?"

A murmur of agreement and Sherlock pushed himself onto unsteady legs, heading straight for his bedroom and leaving John in a state of disbelief that the man was actually going to sleep in his bed.

He shook the thought away, stretched with a groan, turned off the tv and ascended the stairs to his own room. His muscles were tired and heavy but his chest was light with the knowledge that he'd helped calm his eccentric flatmate's fears and that, hopefully, he'd get to sleep in tomorrow.

END

Please review, it makes me feel all warm and fuzzy and stuff.