(A/N): The idea for this piece sprung into my mind fully formed and I knew I had to write it down. Please leave a review if you enjoyed, so I know whether or not to continue.

i.

It is John's fifth night of training in The Royal London Hospital. He is working in A&E: binding cut limbs, setting casts, placing buckets between the knees of the food poisoned, and administering IV fluids to the fevered. The fluorescent glare of the overhead lights give him a migraine, a low occipital twinge that throbs like a vile metronome. He is low on sleep and high on caffeine, his feet ache from hours of unforgiving linoleum, and he is beginning to understand the chaos he will regularly face if he chooses to become a doctor.

There is the physical chaos of injury and illness and gore, but there is also the emotional chaos: distraught parents, weeping friends, spouses who sit in the waiting room praying to a god they formerly did not believe in. John wants to comfort them, all of them. He offers them little plastic cups of water and kneels beside them and tells them what he knows about the dazzling strength of the human body.

It doesn't help.

ii.

He's injecting a little girl with a low dosage of narcotics when a nurse bursts into the room and tells him to come quickly—a victim of drug overdose has just arrived and he ought to witness the patient to learn how to treat such symptoms.

'How old?' asks John, withdrawing the needle from Charlotte's arm.

'Seventeen.'

Only two years younger than me, he thinks. Then he is dashing, running, sprinting down the long corridor and into the main waiting area, heart galloping beneath his ribs.

A cluster of fretful nurses have gathered in the centre of the room, surrounding two men. One looks vaguely aristocratic, wearing a three-piece suit in steel grey with a waistcoat the colour of ash. His ginger hair is receding rapidly for someone with such a young face, but impeccably combed. He is supporting the other man—who isn't actually a man at all, John realises. He's a teenager, gangly and dreadfully thin with protruding cheekbones and halcyon irises encircling swollen pupils. He shifts, staggering slightly in the grasp of the other man's arms. A nurse reaches out to help support his weight and the trio begin walking down the hall.

Their progress is impeded somewhat because the boy keeps stumbling and nearly falling and at one point does fall; a blur of pallid skin and dark curls as he tumbles to the floor.

The nurse looks around and sees John watching them.

'Watson,' he barks. 'Would you mind being of some assistance?'

A frisson of adrenaline slices through John's haze of exhaustion. 'Of course, yeah. Anything.'

He hurries over. Drops to his knees. Helps the patient to his feet.

They stand there, John's fingers curled around the boy's upper arms. He's momentarily embarrassed by the fact that he is only eye-level with the boy's collarbone.

Lanky git.

The boy stares down into John's face with those cerulean eyes. His expression is distant and foggy and he is swaying on the spot, but there is an edge of something else beneath the drug-induced stupor. Something very much like disdain.

Heat floods John's cheeks and he looks away, oddly humiliated.

He feels small.

iii.

No sooner do they reach an unoccupied room when the boy lurches and begins to shudder violently.

The nurse guides him onto the bed fully-clothed and manueuvers him on his side.

He is clenching his teeth and his eyes are rolling beneath closed lids. His extremities jerk and twitch while a shimmering sheen of sweat breaks out on his forehead.

John can see blood flecking the boy's lips—no doubt from his tongue, and watches a sanguine trail of red trickle from his nose, shocking against the pallor of his face.

'Shit,' he mutters and no-one contradicts him.

'Are you incapable of doing anything to improve the situation?' asks the ginger-haired man, his voice tight as he watches the patient convulse.

'There's nothing to be done,' the nurse replies, lunging forward to stop the boy from rolling off the bed. 'We can only wait for it to pass. I'm sorry.'

John counts the seconds and watches as the nurse checks the boy's airways and keeps him from rolling onto his back.

It's like watching someone get electrocuted a million times over.

Horrific.

After what might have been a few minutes, an hour, or a lifetime, the boy goes still. John's air leaves his lungs in a rush of heady relief.

The nurse beckons him over and they peer in and around the boy's eyes and ears. There is no blood to suggest that the bleeding in his nose is from a cranial cavity.

'Your brother will be fine, Mr Holmes,' says the nurse. 'Dr Gordon will be here to examine him in fifteen minutes.'

He glances at John.

'If you have any further questions while you wait, Watson will be happy to answer them.'

Mr Holmes lifts his chin. 'Neither my brother nor I need guidance from a university medical student, no matter how informed you believe him to be.'

John flushes, and the nurse schools his bewildered expression before replying.

'I assure you, John Watson is one of the best interns we've ever had. He is—'

'Not a medical professional,' Mr Holmes finishes. 'Now, please tell Dr Gordon that his patient awaits.'

The nurse nods curtly and leaves, and John can hear him sigh as he strides off.

The room is suddenly unbearably quiet. John casts about for something to say. 'How long has—'

'Please don't feel the need to make small talk, John,' says Mr Holmes. 'Meaningless chatter is far more bothersome than silence.'

So John shuts up, feeling unnerved at Mr Holmes' refusal to address him by his surname. He checks the boy's blood pressure and heart-rate monitors, then smooths a damp flannel cloth over that sweat-slicked forehead, feeling a stab of sympathy when he tenses and moans in discomfort.

'His senses are quite exaggerated at the moment,' says Mr Holmes. 'His brain is expressing the lightest of touches as agonizing pain.'

'I know,' says John, slightly surprised at the man's knowledge. 'Was it cocaine?'

'Yes.'

'This—this wasn't your brother's first overdose. Was it?'

'No.' The elder Holmes sighs, sinking into the polyester plush of the corner armchair. 'His first was eight months ago. Then again three months ago.'

'I'm…' John doesn't know what to say, exactly. '...Sorry.'

'It's his own fault,' says Mr Holmes, glancing at his brother's sleeping form. He seems apathetic, but John feels there is more to the story.

'What's his name?'

'Sherlock.'

John smiles. 'He'll pull through, you know,' he says, inserting an IV tip into the vein shot underside of Sherlock's arm.

He sees a constellation of scarlet dots in the crook Sherlock's elbow. Christ. John swallows hard and finishes what he's doing.

He is treating a seventeen-year-old drug addict. What has become of the world?

iv.

John has an organic biochemistry exam the following morning, the results of which will determine half his grade. He knows this. He's been studying for weeks.

And still he asks Dr Gordon if he can stay at the hospital overnight. With a patient named Sherlock Holmes, to be exact.

Dr Gordon grants him permission.

John makes himself a strong cup of Earl Grey and returns to room 221B.

It's going to be a long night.

v.

The indignant blare of a cab horn cuts through the stillness and John opens his eyes, straining to see in the heavy darkness. He fumbles in his jacket pocket for his mobile and turns it on, cupping his hand around it to keep the glare of the screen from disturbing Sherlock.

It's 3:11 in the morning.

John returns his phone to his pocket, wincing when it makes a loud, electronic chirp. He glances in the direction of the bed, just barely able to make out Sherlock's silhouette. He is curled in a tight little ball, blankets drawn to his chin. He doesn't seem to have woken. His brother, John notices, is absent; armchair sitting empty.

He frowns and shifts in his chair, seeking a more comfortable position. His physical therapist would have an apoplectic fit if she knew he was spending the night sitting on unforgiving wood.

Just as he is drifting out of consciousness, there's a groan from Sherlock's direction.

John is instantly awake. He gets to his feet, pulse thudding in his throat, and shuffles to Sherlock's side.

'Mycroft?' Sherlock's voice is low and rough, vibrating behind John's rib cage like a small earthquake.

John guessed this must be his brother.

'Mycroft's stepped out for a minute, Sherlock. This is John. John Watson. I've been monitoring your condition all night.'

'My—condition?' Sherlock rolls onto his other side, hissing in pain.

'You've had an overdose,' John murmurs, blinking in the darkness. 'You're in The Royal London Hospital.'

'How the hell did I get here?'

'Your brother found you, I think.'

'Fucking Mycroft.'

'Hey, I'm sure he was only trying to help.'

'Wrong. My brother is an interfering bastard.'

John falls silent. He'd thought Mycroft was acerbic, but now he seems positively cuddly compared to his younger brother.

'Why's it all dark?' Sherlock asks, after a moment.

'It's three in the morning. Would you like me to turn on a light?'

'No. It'll make me vomit.'

'Perfectly understandable.'

John drags his chair over to Sherlock's bed and sits, rubbing a hand over his aching temples. 'Can I get you anything?'

'A new skull. Mine feels as if a high-yield atomic bomb has just been detonated inside it.'

John gives a rueful laugh. 'I'm afraid you'll just have to wait for the headache to pass.'

'Headache?' Sherlock sounds disgusted. 'Comparing this to a headache is like comparing a gnat to a hurricane.'

'I'm sorry,' says John. 'If I knew a way to alleviate the pain, I would.'

Sherlock makes a derisive sound in his throat. 'That's not what people usually say.'

'What do they usually say?'

'Piss off.' Sherlock shifts, rustling his blankets. 'They think I deserve it.'

A blend of sympathy and something angrier twists in John's gut. 'I don't.'

There's a pause.

'John?'

'Yes?'

'You're not a doctor, are you.'

'No, I'm a uni student. Med school. I have to get an internship as part of my training.'

'So you're studying to become one.'

'Well, yes.'

'Good.'

John chuckles. 'I'm glad I've got your approval.'

Sherlock begins to laugh but the sound dies in his throat in favour of a tired groan. "I meant you'd be good be at it.'

John feels oddly pleased. 'Thank you.'

Sherlock doesn't reply.

vi.

Daylight is streaming through the window when John wakes next, warming his aching back. He opens his eyes, lashes rasping against cotton sheets. He is disoriented, then mortified, as he realises where he's fallen asleep. He is sitting in his chair, which is still at Sherlock's bedside, but his torso is sprawled on the mattress and his face is in embarrassingly close proximity to Sherlock's groin.

Oh, God.

John eases cautiously back, and sits upright in his chair. A quick look at his mobile tells him it's 7:30. His exam is in an half an hour. Fuck.

There is a flash of movement to his right, and he glances over. Mycroft is standing in the doorway, the handle of an umbrella curved around his forearm. His suit is faintly rumpled but he looks frighteningly composed for someone who just spent a night in A&E.

John's fairly certain he looks like shit. He runs a hand self-consciously through his hair, and clears his throat.

'Morning, Mr Holmes.'

'Likewise,' says Mycroft, fixing John with an odd, inscrutable stare. 'I trust you slept well?'

'Er…' John doesn't know how to respond. 'Well enough. I'm just glad I was able to keep an eye on Sherlock.'

'Why?' asks Mycroft, and there is a bite to his voice.

John frowns. 'I'm training to be a doctor. This is what I want to do with my life. Treat people. Take care of them.'

'You're missing the question, John.' Mycroft steps over the threshold. 'You are a university student with an abundance of exams—one of which is this morning—and I can tell by looking at you that you don't make a habit of staying overnight to nurse patients you've just met and likely will never encounter again. But you stayed last night. You stayed for my brother. Why?'

How can Mycroft possibly know about that exam? Is he some sort of clairvoyant? Bemused, John feels a sudden need to defend himself. 'He's young, I'm young. I related to him. Felt somewhat responsible for his well-being, I suppose.'

'I'll accept that,' says Mycroft. 'But there is a boundary between healer and patient. Mind it.'

John stops, halfway into his jacket. 'Sorry?'

His heart begins to pound.

Mycroft doesn't answer, just smiles an unpleasant smile and takes his seat in the corner.

'Thank you for your assistance, Mr Watson. I'm sure you'll make a very fine doctor.'

John nods, shaking off the sensation of unease. He looks over Sherlock, feeling an odd pang at the sight those riotous curls spilling over his forehead as he rests.

For a reckless few seconds, John considers asking Mycroft for Sherlock's number. But it's a ridiculous idea and he knows it.

So he leaves the room, hurrying to the main office where he signs himself out and slings his name tag on a hook.

When he walks outside, it's sunny.

Somehow that feels all wrong.

vii.

'Holy shit.' Greg takes a sip of his drink, face lit with amusement. "You're telling me she puked on your head?'

'Yeah,' says John. 'Right when I was bending over to get a better look at the gash on her ankle. She's the not the first person with hemophobia I've encountered.'

Greg dissolves into vigorous guffaws and John rolls his eyes. 'Try not to act like a hyena, Greg. It was fucking disgusting.'

'Yeah? Get used to it, mate. That's how it is in the medical profession.'

John decides to change the subject. 'So,' he says, swirling his beer. 'You getting anywhere with Molly?'

'Fuck no.' Greg grimaces, making eye contact with a green-eyed young woman strolling past the bar.

'Out of your league,' mutters John.

Greg flips him off. 'Anyway,' he continues, 'Molly's already going out with another bloke. Jim something or other.'

'Too bad. I thought you two would have worked rather well.'

Looking depressed, Greg launches into a discussion of whether or not he should grow a beard, something he's been considering for quite some time, and John's focus begins to drift.

His eyes wander to the flat-screen TV on the wall, the patina of dried alcohol on the floor, smitten couples kissing messily in corners.

And then his heart stops.

Because Sherlock Holmes is sitting at the farthest table, all dark curls and grey eyes and pale skin. It makes John light-headed.

He swallows and sets his pint down with clenched fingers.

'You alright, mate?'

Greg is staring at John, a pleat of concern between his brows.

"Yeah,' says John, breathless. 'I've just seen someone.'

He takes another look and that's when his heart sinks to his toes, because that isn't Sherlock after all, it's someone else, someone with a rounder nose and higher forehead and larger jaw.

John swears to himself, viciously embarrassed.

It's pathetic how wrapped up he's become in Sherlock Holmes.

He needs to pull himself together. Now.

viii.

There is a certain level of anonymity on the London tube.

John likes it. He isn't a flashy, showy person. He likes a bit of privacy, a bit of space to himself. Despite the effortless warmth that allows him to make friends so easily, constant socializing exhausts him.

When he gets on the tube, he likes to savour the brief respite.

So it comes as quite a surprise, when, halfway between stops, there is a rumbling baritone in his ear.

'Hello, John.'