It's me! I present to you a case fic (slashless, because I'm terrible at writing it), inspired by my best friend's advice to make a story out of a really bad nightmare I had. Canon-typical dark themes and violence. Ya'll know the drill.

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John didn't bother to glance up when something crashed loudly in the kitchen. Well, at the border between the kitchen and the sitting room. He didn't even flinch when a stream of creative curses started spouting out of his brilliant- and hilariously forgetful- flatmate.

"Rosie's sleeping," he called offhandedly, flipping a page in his book.

In response, Sherlock lowered his voice slightly and continued to curse.

"Damn you and your baby-proofing!" The detective hissed from behind John. There was a thump and a dull crash as Sherlock knocked a metal bowl off the kitchen island.

"It'll go away in a minute," John replied.

"You put that damn bar at foot-level on purpose, didn't you?" Sherlock accused. "You knew I'd ram my toes against it!"

"Well, it certainly makes up for the body parts in the fridge. Maybe one of these days you'll stub your toe so hard that it just falls off. One more thing to experiment with."

Sherlock spat out another curse. "I've got more intelligence in my big toe than you have in your entire brain."

"Anatomically incorrect, Sherlock," John shot back. He flipped the page again.

After a moment, the doctor heard the baby gate he'd installed in the kitchen doorway click open and then shut again. Sherlock ghosted past him and then, in an odd contrast to such graceful movements, flopped unceremoniously onto his armchair. His robe fluttered dramatically in the air before resting against his legs.

"I don't see why that has to be there in the first place," he groused.

John glanced up at his best friend and pointed into the kitchen. "Sodium Hydroxide." Then he pointed to his left, where Rosie was fast asleep in Sherlock's room. "Baby."

Sherlock grunted and propped his legs on the coffee table while slouching deeply in his chair and crossing his arms like a child. "She's smart."

"No, she's a bit of an idiot at this point in her life," John amended.

Sherlock grinned slightly. "You're just jealous that her first word was 'lock', aren't you?"

The smaller man scowled. "Technically, it was 'law'."

"Yes. But she was reaching for me at the time. Even you can deduce the meaning of that, John."

John shifted in his chair so his position was mirroring his flatmate's and covered his face with his book. He pretended not to hear Sherlock's laugh.

The two men fell silent for several minutes, reading their respective materials- John was reading a biography on Winston Churchill, and Sherlock a cold case that Lestrade had given him.

Well, John thought that Sherlock was reading.

When John was mid-way through a sip of tea, the detective spoke.

"You're going gray, John."

The man immediately went into a violent choking fit, spewing a bit of tea onto the coffee table. Sherlock, like the arsehole that he was, simply smiled thinly at the sight of his best friend choking in front of him.

"You've... given me all of it," John managed to force out.

Then Rosie began to shriek, in the deafening way that only babies can. John slouched deeper into his chair and groaned, still coughing, with his book now laying flat on his face.

Sherlock scowled, but there was a definite light of humor in his eyes. "Look what you've done. You've woken her up."

"Piss off," John wheezed. "It's your turn to get her."

The man hummed and stood, picking up his ever-present violin and walking purposefully into his room. Rosie slept in there since Sherlock was often awake as it is, and he was better at getting her to sleep. John tended to panic when Rosie was upset.

After a moment, John could hear the detective murmuring to the hiccuping baby. He tended to ramble about his experiments to Rosie, or talk shit about John, but the doctor wasn't going to argue seeing as she almost always fell asleep.

Then Bach started to play. John smiled to himself and took another sip of his tea. Well, the rest of the tea that hadn't been spilt several moments ago.

It was, John thought, a good day. He had managed to get Sherlock to do the dishes earlier, and Rosie- well, Rosie was more or less quiet. It was cloudy and cold outside like it almost always was during autumn, but the usual biting wind that came with the season- and this time of night- hadn't reared its ugly head today. A fire was crackling in the fireplace and all was relatively calm.

If he ignored the faint sound of death metal playing in Mrs. Hudson's flat, that is.

Then, as if fate herself had heard his thoughts, a siren began to scream its way down Baker Street, then there was the sound of tires screeching to a halt right in front of his house. In the other room, the violin music came to a sudden halt. A case? Of course it was a case.

Sherlock tore through the apartment and down the stairs, not even bothering to get his coat.

Barely, over the sound of the siren, John heard his flatmate hiss "turn that off! Rosie just fell asleep!"

Less than five seconds later the siren did, in fact, cut off.

A moment later Sherlock returned with a pale Lestrade in tow. He looked at John wearily. He looked exhausted, his doctor side thought, and... shaken? Yes, shaken. He was white as a ghost and his face was more lined than usual. What had happened?

The DI pushed a thick file into Sherlock's hands. "Donovan's having a breakdown at the Yard, Anderson threw up, and we have no idea what caused this. It's right down your alley."

His voice was softer than usual, like he could barely speak. Sherlock opened the file and frowned at whatever was inside.

"Well, this is new," he murmured.

"Boys?!" Mrs. Hudson called from the bottom of the stairs, a hint of worry in her voice. "What's going on?"

"Um, it's fine, Mrs. Hudson, just a case," John called softly as not to disturb the sleeping baby in the next room. "Hey, can you watch Rosie? We- I think we're leaving."

"Actually, John," Sherlock murmured, "I don't think you should come to this one."

The doctor smiled quizzically. "What? I always come."

"This one..." he sighed. "This one's going to be messy."

Sherlock didn't prevent John from taking the file out of his hands, however. He simply lowered his head and turned to Lestrade. "I'll take the case."

John didn't hear him. His eyes were focused on the pictures in his hands. The first three were grainy, black and white, blurred and over-contrasted. A security feed. It showed a large group of teenagers in their school uniforms... digging a pit. They were all clearly happy, playfully pushing and shoving each other and in one student's case, dancing.

In the second photo, they were facing another student whose arms were spread wide as if in greeting. There was a box beside her.

In the third photo, the pit was full of bodies and the teen from before, the one with the box, was leaving.

On the other side of the file, there were photos that had clearly been taken by Lestrade's team. Measurements of the pit, photos of the shovels used to dig the grave, and photos of the grave itself.

Or, to be more clear, photos of the victims in it.

They were just teenagers, like he'd suspected. Girls and boys. Kids. And they were smiling, as if they were simply dreaming. None of them... none of them were showing any signs of distress. They looked utterly content. They all had numbers beside them. A body count. There were twenty four victims. Twenty four dead teenagers.

Faintly, John could hear Sherlock and Lestrade calling his name.

What had happened? It was suicide, clearly, it couldn't not be suicide, but why? How?

John swallowed hard and forced himself to come back to the present. "Um, poison? What... any ideas on how...?" He managed to choke out, looking up at Lestrade.

The DI shifted his weight to his left and rubbed his face wearily. "We don't know. We- we don't know anything. It was all self-administered, and-"

"Have you located any security feeds showing the self-administration?" Sherlock interrupted.

Lestrade shook his head. "The feed is missing five minute's worth of recordings."

The consulting detective looked at John with something akin to caution in his eyes, which wasn't all that common. "Will you come?"

John had never hesitated on a case before. But this, this was different.

"Um, let me get this straight," he began flatly. "This is a mass suicide?"

"One with a witness that is, I assume, still alive," Sherlock confirmed.

"They... God. Oh my god." John glanced in Rosie's direction, his hands clasped behind his head. Somewhere in London, right now, there's at least forty parents and god knows how many friends and relatives finding out that their sister, their son, their best friend is dead. Dead in a pit. And they'll never come back. What if it had been Rosie?

John shoved his left hand in his pocket to halt its shaking before it even started. "What makes you think that it wasn't just... a bunch of freak planned suicides? You must think that there was another motive."

The question was directed towards Lestrade, but Sherlock answered it for him.

"The kids didn't have records of suicidal ideation, I assume. Look at their uniforms. They go to a highly advanced public school, so they obviously had good lives ahead of them. There is no clear motive for this and therefore, something's wrong."

"We could use your help, Doctor Watson," Lestrade said softly.

John was silent for a moment as he regarded the two grim men in front of him. There was Sherlock, with his coat in one hand- when did he get that?- and a gleam of interest in his eyes, and the ever-tired Lestrade. He looked haunted. He couldn't turn this down, not something as twisted as this.

The doctor sighed. "Let me get my things."

~

Constrictive criticism is always appreciated! This is my first Sherlock fic, so please feel free to give me tips/correct things! Please review!