"John."

A small, unhappy noise escaped John's throat. He didn't open his eyes. It was a cold, damp night, the chill of the air settling into his bones with an ache, and he had been awake for nearly thirty straight hours, struggling to keep up with Sherlock's manic hunting through London's gray streets. Whatever Sherlock wanted, it could wait.

"John."

"Mm." John tucked his chin down further into his collar, hoping Sherlock would get the point and leave him alone.

But then, Sherlock was never one for subtleties. "Joooohhhhhnnnn."

John's eyes snapped open, his gaze wandering blearily up to Sherlock's impatient face. "What, Sherlock? What is so ruddy important?"

"You're sleeping," said Sherlock, in a tone that suggested both childish petulance and the impatience of a genius.

"Excellent deduction, Sherlock, I'm glad London's got you on her side." Closing his eyes once more, John tucked his face into his shoulder and yawned- but Sherlock wasn't having it. He tapped John's forehead with one slender, gloved finger.

"This is a stake-out, not a slumber party," he hissed, his pale eyes narrowed. "You need to be on the alert."

John yawned mightily. "You don't need me watching. Trust me: if something happens that your eyes miss, I'm not going to be the one to catch it."

"Yes, but…" Sherlock sighed moodily. "I can't very well talk to you if you're sleeping."

"Yes, you can. You do it all the time."

"John." There was an almost pleading edge to Sherlock's voice, and John knew before Sherlock finished his sentence that the words he dreaded most were coming next: "I'm bored."

Huffing a bit, John sat up and rubbed the bleariness from his eyes. "Bored? How can you be bored? We're on a case! Right inside that restaurant, two men are conspiring to fake a séance and swindle some poor old woman out of her widow's pension. How can that possibly bore you?"

"They're taking too long!" Sherlock whinged. "I've a mind to go in there and rough them up a bit, get them to talk-"

"No, no, we're not doing that." John rubbed a hand down his face, stifling another yawn. "Okay. Okay. How about I tell you a joke, hmm?"

Sherlock sat back, his arms folded across his chest. "No, all your jokes are rubbish."

"Okay," John said, his teeth clenched, "then how about…well, we can discuss the case."

"Nothing to discuss." Sherlock's fingers began to twitch. "The men will lead us to the head of their little operation within the hour, I'm sure of it."

Annoyed, John drawled, "Then why don't I recite some poetry for you? Or maybe you'd prefer a juggling act. Oh, I know, I could cartwheel down the alley. Would you like that?" Sherlock seemed to be considering the last option until John seethed: "I was joking, Sherlock."

"Then just talk," Sherlock said softly. "My brain needs constant stimulation in order to function at its peak. A dark alley, a noiseless night…I can't deal with it! I need an outside stimulus to keep me sharp."

"I see," John said, in a tone that suggested otherwise.

"So…stimulate me!"

John chuckled, and Sherlock pulled a face. "You know what I mean."

Settling back against the wall, John racked his brain for something to talk about. In dozing, his mind had wandered to the girl at the coffee shop, her dark curls and long, white fingers affecting him poignantly. Now he thought about the night watches he'd been on in Afghanistan, and laughed a little to himself as one particular memory swam to the surface.

"What?" Sherlock asked, eager for some small distraction.

"I was just thinking about what the boys and I used to do during watch, in the war," John smiled, his eyes focused not on the street before them but on the desert of his mind, the dim cast of the streetlight above them taking on the greenish hue of his memories. "Everyone did rounds in guard duty when things were stagnant. One night- we'd been weeks without action, and everyone was getting a bit edgy, y'know- so one night, my mate Williams turns to me and says: 'Twenty quid and I'll take off every stitch I've got on and run one lap around camp.'" John shook his head and chuckled. "I said 'What?' and he repeated himself. 'You're a crazy bastard,' I said, which was true. 'You'll get shot. If they can't see your uniform they'll assume you're the enemy.' Long story short, I took the bet and lost twenty quid. You should've seen the maniac, running about with his hands over his head, bare arse glowing like the moon. He was mad, absolutely mad. I guess we all were, then, but he was the worst of us."

"Was," Sherlock said gently. "You said 'was'."

John blinked back into himself, into the present. He'd forgotten Sherlock was even there. "Yes. Yes, I did."

"When did he die?"

"A few months later." John swallowed, his throat raw. "Firefight in a small village. The…the Hajjies were hidden down in a secret cellar. Williams and his team were the ones to find them."

Sherlock reached up and brushed a tear from John's cheek was his thumb. The move was so casually intimate that it distracted John from the fact that he'd been crying at all. He realized his breath was ragged, his burning eyes unable to focus on anything. "I-I'm sorry," he stammered, embarrassed by the roughness of his voice. "I don't talk about the war."

"I've kept you awake too long," Sherlock tutted. He leapt up and extended a hand down to John, his expression softer than John had ever seen. "Come on," he said, as John took his hand and stumbled to his feet. "Let's go home."

"What about the case?" John muttered, wiping his face with the back of his hands.

With a guilty look, Sherlock confessed, "Merely a distraction. I concluded about four hours ago that the first 'victim' was actually the head of the ring. This," he said, spinning his fingers, "was just a way to gather proof."

"You absolute bastard," John laughed, his eyes still stinging.

Sherlock slung his arm over John's shoulder. "Oh, but what would you do without me?" He touched his chin to the top of John's head before leading him, John's tired bones barely cooperating, out to the main street so John could hail them a cab.

[A/N: Apologies if anyone takes offence to the term "Hajjies". It's not one I use myself, but I know it to be the term soldiers tend to prefer when referring to enemy combatants. I thought using that term would make it more obvious that John had almost slipped back in time, his PTSD still acutely affecting him though in a less obvious form than his psychosomatic leg injury.]