Chapter Text
The trench mud had long since dried on John Watson’s boots, but it remained in his bones, a silent reminder of the months he had spent wading through blood and filth. It clung to him in ways he could not shake, even here, far from the front, in the dim corridors of a British intelligence outpost hidden beneath a countryside estate.
Officially, he was here to recover. His shoulder still ached from the bullet that had sent him back to England, though it was not his body that suffered most. The War Office, however, had little patience for convalescence. He was still useful, they told him, handing him a dossier with a name he recognized but had never expected to see in military records.
Sherlock Holmes.
John had read of him once, years ago—a man who had, in peacetime, amused himself by solving crimes in London, unraveling the secrets of the city with unsettling ease. Now, it seemed, his skills had been repurposed. The War Office had tucked him away in this bunker of an intelligence station, cracking German codes, dissecting enemy intelligence, and generally making himself impossible to work with.
John had been sent, in no uncertain terms, to keep him in line.
He sighed, rolled his shoulder, and knocked on the door.
There was silence for a beat. Then—
“If you’re here to deliver another dull memorandum from Mycroft, set it on fire and save us both the trouble.”
John exhaled slowly. “Not a memorandum. Not from your brother. Can I come in, or shall I conduct my duties through the keyhole?”
A pause. Then, begrudgingly—“Enter.”
John pushed open the door.
The office was a disaster. Papers littered the floor, covered in frantic, scribbled calculations. Maps of Europe were pinned haphazardly to the walls, circles and lines drawn over them in ink. A phonograph sat in the corner, a record spinning lazily, filling the air with faint violin music.
And in the middle of it all, perched on a chair with one knee drawn up, sleeves rolled to his elbows, was Sherlock Holmes.
He did not look up.
John cleared his throat. “Captain John Watson. The War Office has assigned me to assist you.”
Holmes twirled a pen between his fingers. “Ah. Another soldier. They do enjoy sending me soldiers.”
John bristled. “I’m a doctor.”
At that, Holmes lifted his gaze.
John had expected something sharp, something dismissive, but the scrutiny in Holmes’s eyes was surgical, dissecting him in an instant. A flicker of interest crossed his face before he leaned back, gesturing vaguely.
“Yes, I see that. Fifth Northumberland Fusiliers. Wounded, but not recently—you no longer favor the shoulder. You’ve been at the front long enough to grow disillusioned, but not so long as to lose your sense of humor entirely. And—” he sniffed, “—you had tea before coming here. Terrible tea. Army-issue. My condolences.”
John stared. “How—”
Holmes waved a hand. “Simple observation. If you’re to be my keeper, at least tell me you’ll provide better conversation than the last one. He had the intellectual curiosity of a boiled potato.”
John crossed his arms. “I could leave you to your own company.”
Holmes grinned, something almost genuine sparking in his expression. “Where’s the fun in that?”
And so it began.
Days blurred into weeks. The work was relentless—deciphering intercepted German transmissions, untangling shifting codes, tracking enemy movements through scattered fragments of intelligence. John, though initially uncertain of his role, found himself drawn into it. His medical training had honed his patience, his ability to see patterns in chaos.
And Holmes, for all his brilliance, was utterly impossible.
He worked for days without sleep, muttering to himself, his mind moving too quickly for his own good. He spoke in riddles, dismissed orders with casual disdain, and regarded most of his colleagues as though they were particularly dim-witted schoolchildren. He also, John discovered, had the eating habits of a starving stray—entirely neglecting meals until John set them in front of him with an exasperated look.
It was maddening.
And yet.
There were moments—small, fleeting—where John caught glimpses of something beneath the arrogance. The way Holmes’s hands trembled, ever so slightly, after they cracked a particularly vital code. The way he would stare at a transmission for hours in absolute stillness, eyes dark with something too heavy for words. The way his sharp wit softened, ever so slightly, in the rare moments of quiet between them.
Their arguments turned into discussions. Their discussions stretched into long nights, bent over ciphered messages and half-drunk cups of tea.
And somewhere in the margins of their work, something unspoken settled between them.
John felt it in the way Holmes lingered when passing him a paper, fingers brushing his own. In the way his gaze caught on John’s mouth when he smiled. In the rare moments when the world fell away, and it was just the two of them, a breath away from something neither dared to name.
But war did not allow for sentiment.
And war, in the end, found them.
It happened fast.
A German spy had slipped into the compound. Whether by luck or calculated treachery, he had made it to their offices, pistol drawn. John saw the glint of the gun first, saw the angle, the trajectory.
He moved without thinking.
The shot rang out.
Pain bloomed in his side, a dull, burning thing, but he remained standing.
Holmes was at his side in an instant, pressing hands over the wound, his face pale with something raw and unguarded.
“Idiotic,” he snapped. “Reckless, sentimental, idiotic—”
John exhaled a weak laugh. “You’re welcome.”
Holmes did not smile. “Stay awake.”
John wanted to say something clever, something lighthearted, but the world was already slipping out of focus.
When he woke, he was in a hospital bed, arm bandaged, throat dry. The War Office man stood at his bedside, expression unreadable.
“You’re being reassigned,” the man said.
John’s stomach dropped. “No.”
“Your presence here is compromised. You leave for France in two days.”
Holmes did not visit. Not at first.
But the night before John’s departure, his door creaked open. A shadow slipped inside, moving like a ghost.
Holmes.
John sat up, wincing. “You’ve been avoiding me.”
Holmes hesitated. “I dislike farewells.”
John exhaled a breath. “Then let’s not have one.”
Holmes studied him, something unreadable in his expression. Then, without a word, he pressed a small, folded slip of paper into John’s palm.
“If ever you should need me,” Holmes said, voice quiet, “you know where to find me.”
John swallowed hard. “Sherlock—”
Holmes shook his head. “Not now.”
And then he was gone.
Years passed. The war ended. London felt different. Or perhaps he did.
One evening, while sorting through an old trunk, John found the slip of paper.
His breath caught. He unfolded it, hands trembling.
A coded message. Simple. Neat.
221B Baker Street.
The street was the same as it had always been.
John hesitated on the doorstep.
Then, finally, he knocked.
There was a beat of silence. Then—
“If you’re selling something, I’ll have you know I have no interest—”
John smiled.
“I’m not selling anything.”
Silence.
Then, the door opened.
And for the first time in years, John Watson was home.