Sherlock did not go back to bed, despite John's insistence, so he gave up the sofa for Sherlock to sprawl out on in hopes that his friend would at least manage to snatch a few minutes of sleep here and there.

John didn't sleep, just sat in his chair and stared idly towards the muted TV. The minutes ticked by into hours. The clock clicked to five past five. John was looking forward to daybreak. He was hoping that it would help him wake up a bit. He went to make himself a coffee and trailed tiredly back into the sitting room, pausing when he glanced at Sherlock.

He hadn't uttered a word since crawling onto the couch, hair still damp from the shower, three hours ago, but John was never positive that he'd been sleeping and now there were lines of pain etched onto his face.

"... What's happening?" John asked softly.

"Stomach," Sherlock replied briskly, pressing his lips into a thin line.

As John watched, Sherlock's leg twitched, prompting Sherlock's jaw to tighten before he pressed his bare feet into the armrest firmly. He'd been sweating ever since immediately following the shower, John reckoned, but now he was shivering, too, and it was only just that John bit his tongue against the horrendously pathetic drivel that he desperately wanted to spew forth. Sherlock wouldn't appreciate the sentiment, but John hated seeing him like this.

Sherlock's fingers seized at the front of his own shirt, knuckles gone white for a half second before relaxing again. John closed his eyes briefly, then shook himself and straightened up.

"You want the heating pad?" There had to be something proactive to do, and from the squirming Sherlock was doing in trying to get comfortable on the sofa, his entire body was probably aching as well as the cramps probably ravaging his stomach.

"I don't care." Sherlock tossed his head on the armrest. "Nothing helps."

Like that's going to stop me, John thought. "I'll be back in a minute, try to relax."

Sherlock's jaw tightened again, and John wondered if he was biting back a retort. He didn't care. It would get worse, he imagined. Still, he searched out a heating pad and some more paracetamol, taking them both to Sherlock. The detective swallowed the pills with the smallest sip of water and pressed the heating pad against his stomach, even as it was still wasn't heated and John was plugging it in.

"How many hours?" John asked quietly.

"... Twenty... twenty one... don't remember." His fingers twitched.

John nodded. "Okay." He nearly reached over to brush Sherlock's curls out of his face, stopping himself at the last second. Touchy feely was not going to get either of them anywhere. "Okay," he repeated, clenching his hand into a fist before turning away. "Let me know if you need anything."

"Morphine." Sherlock laughed, a strangled sound that sank into John's ears that he was positive he wouldn't forget any time soon. "Oxycodone. A sedative."

John paused. "... You know I can't do that."

"You asked," Sherlock bit off, and rolled over to face the back of the sofa.

"Fair enough," John muttered, heading back to the chair.

Dawn broke as bright and early as it usually did, with Sherlock inhaling and exhaling breathily on the sofa. He seemed to have dropped off at some point in the past couple of hours, although John could never tell if he stayed asleep for any decent amount of time.

Instead of the morning news, John was watching him sleep.

He nibbled at a piece of toast with jam on it, feeling vaguely sick to his stomach himself. Every few seconds, Sherlock's extremities would twist and jerk as though connected to an invisible string, pulled at whim by the tiny, most powerful thing John had ever witnessed. Sweat had soaked through his thin t-shirt, staining it dark in the curves where it clung to his body. As John sat by helplessly, Sherlock tossed and turned on the sofa, curling tightly into his body and staying there as he shook in unconsciousness.

The detective awoke with a gasp some time soon thereafter, his arms immediately going to his stomach. "Oh, fuck."

"You're a whole day in," John said shortly, not giving him a good morning or a how are you. He knew that those would irritate Sherlock even further.

"Don't tell me that!" Sherlock snapped, swinging to his legs off the sofa while simultaneously still managing to keep his body tucked in the smallest space possible. "Not when it doesn't peak for two to four days!"

"Sorry," John said emotionlessly. He knew that. He knew that detox didn't happen overnight. If it did, anyone who went through everything combined into one day would be dead. Even this way, detox still killed people; John prayed that Sherlock didn't start seizing, for one, or that he didn't go for knives or blades or anything that could hurt him in the heat of the moment. He'd already taken all the pills - all the pills, even the paracetamol - from the bathroom cabinet, because if Sherlock wanted a high or an out, he would probably take anything to get him free. If he'd chance a poison pill just because he was bored...

Sherlock thumped his head back against the back of the sofa. "Coffee. Decaf. Tea. Anything."

"Right." John went to brew a pot, leaving Sherlock to struggle with his sweat soaked shirt on his own. After the coffee, a brew that John double-checked was decaf, was ready, he went back to the kitchen to find a suitable bowl to fill with cool water and a flannel. "Here," he said, setting both down carefully on the coffee table.

Sherlock regarded the water pensively, his fingers clutched around his mug of coffee and his other arm still wrapped around his stomach.

"Cool water," John supplied. "For-"

"I know," Sherlock interrupted, although it lacked a little bit of the snap that it had had in moments prior. "Thank you."

John smiled sadly. "Yeah."

Sherlock stared into his coffee for a moment, seemingly to contemplate the dregs of it. He narrowed his eyes slightly as John retreated back to his chair, but then he drank the last of it in a few, small sips and set the mug aside.

"Sorry," Sherlock said shortly. His tongue sounded like it was stuck to the roof of his mouth. He leaned forward, dipping his fingers into the water to fish out the cloth. "I'm being entirely serious when I say it's how I would imagine Hell." He wrung the cloth out and pressed his face into it, sighing heavily. "It's like... having a bad trip while being run over by a bus then being thrown into a vat of oil and then being set on fire." He rubbed his face and then pushed the cloth back through his sweaty hair, pushing it from his face. "... And then it repeats. Over and over." Sherlock twirled his hand in a clockwise motion, then stopped and made a face. "I don't usually create metaphors about life."

John shook his head. "Look, you don't have to explain."

"I think it's necessary," Sherlock said. His tone was point-blank; it didn't lose effect by the red-rimmed eyes or the runny nose or the flush on his cheeks. "It is necessary."

"It's not you talking, it's the drugs." John shrugged slightly. "I know that. Come on. I've known you for years. I know you."

Sherlock's head fell a few degrees to the left. "Do you?"

"Yes," John said determinedly. "I do."

Sherlock stared at him with a frighteningly intense gaze. Beneath the hazy look and the curls matted to the side of his head and the shaking hands and curse words, he was doing that look that made John squirm on the best of days. It was like he was looking directly into his soul. It was the most clarity that John had seen in Sherlock's eyes since he'd gotten here last night.

Then, Sherlock scoffed and turned away, thumping his head back against the sofa again. He draped the cool cloth over his face and left it there.

John wasn't sure if he had passed the inspection or not.

"You should go back to bed while you can. Or at least eat a little something," he said instead, standing again.

"The cramping's already on, I'm just going to vomit it back up," Sherlock said. "Not to mention it's getting worse."

"Still. Piece of toast? Something, Sherlock?" John wheedled.

Sherlock sighed thinly. "Toast, no jam."

"Good-" John stopped himself from finishing that thought. There was no reason - asides from the obvious, but he didn't want to give into that - to coddle Sherlock. "Yeah. Just a second."

When he returned a moment later, he nearly dropped the toast when he took one glance at Sherlock's exposed back. He'd fought his shirt off minutes earlier, but now he had curled up with his head on the armrest again. His face was tucked into a cushion, but his back was bared to John.

And he had scars. Large scars, along the length of his back, where the nodules of his spine pressed against his skin, like he had been beaten. Or tortured.

John sucked in a deep breath. "Sherlock... what happened?"

"Mmm?"

"Your back..."

"Oh." Sherlock sat up slowly, rolling over onto his back (so they didn't hurt, then, that was good. John could tell they weren't recent, but those hadn't been there before Sherlock had gone away.), and then his opposite side. "Yes. It's fine."

John blinked rapidly and then handed over the meagre breakfast. "... Why didn't you tell me?"

"I was away, you thought I was dead." Sherlock's voice was dismissive, but also subtly guarded. If John didn't know him, he wouldn't have noticed it.

"Why didn't you tell me?" John repeated. Why didn't you tell me when you came back, when we got back on speaking terms, any of this time that I've been spending with you?

Sherlock took a small bite of the toast, meeting John's gaze. "Just like you, even I have scars I don't talk about." He looked away towards the window, where the sunlight was filtering through at a slant that caught the dust, chewing his breakfast methodically.

John had to remind himself to breathe again. It was a perfectly sound response. John had never offered up explanation for his own scars, and the only way Sherlock had ever gotten a story out of him was when he'd had to bandage a knife wound on John's back after one memorable case. Even then, John hadn't been very forthcoming about the details, except an IED, Bill Murray, and "I got shot". Sherlock hadn't pursued it; John was tactful enough to know that the same standard was in play here, and he had no right to ask.

Didn't mean he didn't want to know. And it didn't help the twinge of sadness in thinking that, after so long, there were still things between them that they couldn't bridge the gap over. Maybe one day. Things had changed so much, and, knowing their lives, they probably would again in the sometime probably-not-so-distant future, but still...

One step at a time, then.

"Right," John said quietly. He straightened his shoulders. "I'm going to change out your linens, and then you can go back to bed. Try to catch some more sleep."

Sherlock nodded without a word.

One step at a time.

There's quite a few more elements here than just the detox itself, so do bare with me while Sherlock's symptoms kick in and fluctuate. You can only write the "peak" of detox with so much detail without getting repetitive, so I've paced the story where I thought middling level was.

As always, thank you for your support! Rather a dark venture, but definitely a lot of hashing out to be had after S3. Stay tuned! :)