For an amateur—no, consulting—detective, Sherlock Holmes had nothing to do. It wasn't that there wasn't any crime in London, it was just that a) very few people bothered to consult him, and b) he'd probably be bored anyway. So for right now, he was playing his violin, trying to ignore the relief he used to get when he took cocaine to the arm. He'd been clean for three years. He wasn't going back.

Morning turned to afternoon, and afternoon to evening, and still Sherlock played. He wasn't composing, he wasn't performing, he was just sort of running the bow along the strings, idly keeping in practice. He mused over the fact that it had been those three years since he'd left university—it got boring, the drugs numbed it, and what was the point of it, anyway? Admittedly, if it hadn't been for university, he would never have made a friend of Victor Trevor, would never have been invited to his house for dinner, would never have decided to become a detective. But it was just so…boring. So repetitive. And leaving hadn't been that much better. He had business cards, now, a mobile phone, a place to live. But nothing to do. No clients, not one. Not for anything exciting, anyway—he'd solved half a dozen missing persons cases, three robberies, and two rather open-and-shut murders, but nothing he could really sink his teeth into.

In a heap of dysphoria, he slumped down onto his chair, setting the violin aside in favour of the television. "Boring." He groaned. London, of all cities, and nothing to do. He was so desperate, he even thought of calling his brother Mycroft just for a casual chat, but decided against it. He switched the television off and got dressed. If nothing else, he could go for a walk. Maybe keep his observation skills sharp.

It wasn't the nicest part of town he was living in, but he didn't really mind. The stench of garbage and pollution was something that not many people noticed on a daily basis, but it was there in the wind all the same—Sherlock could make out every component. He enjoyed it, knowing that at any moment, there might be a robbery or a mugging or a murder not two blocks away. Knowing he'd be close to the action. He pulled his coat around him—for springtime, even, it was a chilly evening, and he had never been fond of cold.

He set off in a random direction, intending to lose himself in thought, and so he did for three hours, just walking. Something familiar brought him back outside of his head—he knew this place. He was just a few blocks from Victor's house.

"I know it's a bit strange to invite you to see my dad."

"Why?"

"Well…we're not really that close. I mean, yeah, we're friends, but we've known each other for some time, and I still don't know anything about your family and you don't know anything about mine."

"Your parents are separated, though not divorced, and you have a younger brother. Moderate income."

"Well…yeah, okay."

Sherlock narrowed his eyes at the memory. While it was true that the only fact the two shared was that of having no other friends, he had found himself growing attached to Victor. Sirens and lights pierced Sherlock's cloud of thoughts. Two squad cars were heading down the street—towards Victor's house.

Sherlock broke into a run, grateful he'd brought business cards with him, something to give him access to crime scenes. Sentiment induces fear. Useless to worry. Probably not Victor. He rounded the corner to find the squad cars outside Victor's house. Still not certain to be him. People move. They change jobs, change cities. He marched up the stairs, fingering his card in his pocket, ready to show it if need be.

"Do you think you'll be able to show off to Dad?"

"Of course. Why would it be any different to demonstrate my skills to him?"

"I just want him to think I have good friends. I'm not exactly a social person."

"I'm sorry, sir, this is a crime scene." The young officer put his hand across the door frame, keeping Sherlock out.

"Yes, and I'm a detective," Sherlock replied, taking his card out and taking advantage of the officer's distraction to go inside.

"Sir!"

"Dad, this is Sherlock Holmes." Victor's father raised an eyebrow as Sherlock shook his hand, faking a smile.

"The famous Sherlock Holmes?"

"Hardly famous."

"From what Victor says, I'm surprised." Mr. Trevor smiled and beckoned Sherlock inside. "Come out of the hallway, dinner will be ready soon."

Nothing had changed. Not the furniture, not the décor, not the pictures on the walls. This was still the Trevor residence, though going by the smell, Victor's mother had returned. There had also been gunshots fired. The policeman still followed Sherlock, trying to get his attention to make him leave, but DI Gregson, who had worked with him before on a murder case, recognized him and told the officer to let him stay.

"What have you got?" Sherlock still stood in the hallway, half-intimidated to go into the living room. Why am I nervous?

"Murder-suicide," Gregson said. "How'd you find us? We've only just got here ourselves."

"Was in the area." Sherlock slid on a pair of latex gloves and stepped into the room.

"So, Mr. Holmes—may I call you Sherlock?"

"Why wouldn't you?"

"Er…so, Sherlock, I hear you're good at telling a man's life from a look. What can you tell about me?"

"You've recently been threatened—within the last year, are a former amateur boxer, worked in manual labour, visited New Zealand and Japan, and were extremely good friends with someone whose initials are J.A. whom you now wish to forget entirely."

Mr. Trevor stood from the armchair and made it several steps before outright fainting.

He lay in the same place now. The only difference was the blood. Gunshot to the chest, exit wound on back. The same was true of Mrs. Trevor, three feet away, and the teenager on the other side of the room. Sherlock shook down a sensation of illness—for some reason, it was different when it was someone you'd met, even if you'd only met him once. He looked to the wall beside the door.

Please, God, forgive me. I never will.

The handwriting was unmistakable. It was shaky, and written under great stress, but it was unmistakably Victor's hand. "That's the murder victims. Where's the suicide?" He already knew who it was, already felt his stomach twisting. Caring is a fatal flaw. Don't start now.

"Up here." Gregson led him to the landing on the stairs where a man of Sherlock's age sat slumped against the wall with a gun in his hand and a hole in his head. "Name is—"

"Victor Trevor." Gregson looked surprised. "It's not magic, Detective Inspector," Sherlock snapped. Stop. Keep emotions away.

"…oh." Gregson must have seen something in Sherlock's face that he'd never seen before. Sherlock was kneeling by the body, examining it. He'd expected to feel something stronger, something different, something more than just mild shock at the idea that his first and only friend killed his family and then himself.

"Quite certain this was the weapon in the other murders?" He couldn't tear his face away from Victor's cold, dead eyes. Why?

"Not until we run ballistics, but that's where everything's pointing."

Sherlock looked up from his studies. There was a stranger there.

"Do you mind if I sit here?" The stranger gestured to an empty seat beside Sherlock.

"Why would I mind?"

"I…don't know."

"Then why did you ask?"

"To be polite."

"Waste of time."

"Oh." The stranger sat and pulled out his own book. To Sherlock's astonishment and gratitude, the stranger didn't attempt to continue the conversation. Far too many people had started a train of thought, broke off at Sherlock's insistence, but kept going, kept pushing. This one didn't.

Sherlock handed Gregson his card and headed home. "Call me when you get more information."

"Er…okay."

Sherlock left Victor's house and hailed a cab to go home. It wasn't worth another three hours of walking. Something bothered him about this case. The evidence was simple, obvious, but the emotional component left him flustered. Normally he only bothered with such evidence as a psychological curiosity, a bonus, but right now, it was everything.

"Uh, well, you see, I don't really have anyone to study with, Mr. Holmes." Victor had waited until the fifth encounter to approach.

"I find solitary studying more useful. Fewer distractions."

Yes, Victor had always been distant, always been a bit strange, but Sherlock couldn't think of any reason he'd be outright homicidal, let alone suicidal.

"No." Sherlock sighed as he caught sight of his companion's notes. "That's completely wrong."

"Is it?" Victor frowned at the paper.

"Yes. Two hydrogen bonds. Not one."

"Oh?" Victor continued to stare at it. "Oh!" He erased his lines and fixed them. "Thanks."

"I'm only attempting to make sure at least part of the world is correctly educated."

When he thought Sherlock had looked away, Victor smiled.

Sherlock paid the cabbie and went inside to his musty old flat. He shouldn't remember—he didn't want to remember. Remembering would skew the facts. Sentiment always did.

"You like Tchaikovsky, too?"

Sherlock hadn't realized he was lightly humming. "Yes."

"Are you going to the concert tomorrow?"

"Yes."

Victor packed up his books, late for dinner. "I guess I'll see you there."

Sherlock sat on the sofa, staring at the ceiling. Stop remembering. A little corner of his mind told him exactly what it was that would keep him focused, keep him on-track, keep his mind at top speed, but he'd promised Mycroft he'd never be a slave to that again.

"Are you okay? You seem…high."

"I am."

"…okay." Victor was clearly uncomfortable with this. Sherlock had been speaking even more rapidly than he was used to, permitted him to see him in less-refined states now that they'd been spending more time together outside the study halls. It was the first time Victor had dropped by out of the blue to see Sherlock in this state. "No, it's not okay, what are you on?"

"Close the door." Victor did as instructed and approached Sherlock. He sat down in front of the sofa, and looked at Sherlock worriedly.

"No, really, Sherlock, what did you take?"

"Benzoylmethylecgonine," Sherlock responded with a grin, sitting up suddenly, dilated eyes staring straight at Victor, straight into his soul.

"What?"

"Don't be an idiot. You're relatively good in chemistry. Consider this a pop quiz. Or, alternatively, consider it a pop quiz in pharmacology. Either one." Sherlock searched Victor's face for understanding.

"Sherlock, you're not supposed to—if they find out—"

"Oh, they're idiots, they haven't found out yet, why would they now? Unless you tell them." The look was accusing and pleading at the same time.

"I won't tell. You're my friend. I wouldn't betray you."

Sherlock frowned. But this is the betrayal. This suicide. "Why?" He continued to stare at the ceiling, thoughts fragmented at best, half of his mind trying and failing to ignore the memories, desperate to find some motivation.

"And, from the audience, we need a travel method!" Hands were raised all over the audience of the black box. Victor had finally worked up the courage to think of something. Sherlock had thought of far too many, but viewed the whole affair as pointless—improvisational comedy was not his favourite of theatrical arts. They actually called on Victor.

"A flying television," he said, loud enough for the presenter to hear but no louder. She laughed gratefully.

"No one has a mind quite like Victor Trevor." She'd been his theatre professor—Victor was an avid scriptwriter, so she knew him well.

Sherlock hadn't realized he'd fallen asleep until the phone rang. Gregson.

"We got the ballistics back. It was the same gun." Sherlock didn't stick around to listen any more, hanging up right then. That was it. Proof. Oh, there were dozens of ways it could have been faked, but to Sherlock's eye, it was genuine. Victor had done it. Victor had killed both his family and then himself.

"Why?" When Sherlock had known him, he showed no sign of being capable of such an act. Yes, everyone has their breaking point. Everyone has something that could push them to murder. But Victor would have needed to be pushed hard. He called Gregson back. "I need the crime scene photographs."

"But—"

"As soon as possible."

Gregson sighed, rather annoyed. "Fine, I'll have them sent around ASAP."

"Good." Sherlock hung up and paced frantically until they arrived. He tacked them to the wall in a panorama of the house. His phone rang again, and this time it was Mycroft. "What?"

"Are you alright, Sherlock?"

"Yes."

"You shouldn't be."

"I'm a scientist—I'm working it out, solving the problem, detaching myself from the emotions of the situation. Go away. I'm working." He hung up. The evidence was clear. He'd get nothing from that. He called Gregson again. "Get me Victor Trevor's medical files. Oh, yes, I know it's private, but I'm one of the investigators and I need everything, and besides, he's dead; I don't think he'll mind." Twenty three years old and hip deep in the investigation of his own friend.

His friend.

His only friend.

The only friend he'd ever had.

Sherlock ripped the photos off the wall. "Why?" It was the only line of thought that was in his head, the only thing he could think about, and it was numbing, blinding out all ability to think.

"You're doing what?"

"Leaving school."

"Why?"

"Got boring. Got everything I needed from it. The professors turned into idiots and more than once I've ended up teaching class myself."

"Sherlock—"

"It's my choice, Victor. You're hardly going to talk me out of it. I'm leaving at the end of the semester." He'd never seen anyone look so shocked.

He was pacing again, waiting for the papers to come in. He'd known Victor had suffered from severe headaches, possibly even small seizures in the brain—dozens of EEG tests had been run but he never told Sherlock the results. Maybe that's what did it. Maybe he'd had a neurological misfire.

The doorbell rang and Sherlock was there in an instant. He yanked the file from the officer without so much as a thank you before slamming the door in his face. He ripped it open and resumed pinning the paper to the walls. "Why?" No mention in his medical files of what caused those days when Victor was too ill to come to class. It seemed idiopathic—no known cause. He stared at the pages of photographs and charts and detailed medical reports, but nothing gave away why Victor would have done this. He felt his mind going blank every time he failed to see the people in the photographs as just people. Why is detachment so hard? I need to think. Mycroft be damned.

He threw on his coat again, marched outside, and searched for the nearest distributor of cocaine. He found one and, completely without trepidation, handed over the money and took the supplies back to his flat. He shut his eyes, more than a little aware of the bite of addiction and how much he hated it, but he couldn't ignore it any longer, the need to think. He tied the tourniquet, adjusted the needle, and for the first time in a long time, depressed a plunger on a syringe that was stuck inside his arm.

It went on for days. The cocaine kept him awake, kept him conscious, kept him focused, and every time it would wear off, he couldn't think again and the flashbacks continued. Every so often, someone would come with a new piece of evidence, a childhood therapist, a previously-undiscovered medical report, a tox screen, the autopsy papers that Sherlock had insisted on.

The fifth day, Sherlock was exhausted and no nearer figuring out why Victor had done what he'd done. He needed more and more cocaine more and more often to fight the emotions and the blinding shock of the situation. He was addicted again, he knew it, but right now, he didn't care—he had to figure out what happened to Victor. He injected again and lay back onto the sofa, the collage of evidence on his wall more than memorized. He would have seen it in his sleep if he'd bothered to sleep. He shut his eyes to think.

"Sherlock, are you high again?" This time, it wasn't a flashback. Damn it. Hallucinations. "You are, aren't you?"

"Yes." Sherlock's eyes snapped open, and Victor was standing there, covered in blood, standing perfectly still and never blinking.

"Why?"

"Had to think." His head was getting fuzzy. "Why did you do it?"

"I don't know."

"Obviously. You're a fabrication of my mind. Go away."

"I can't," Victor said, raising his hand to his head and putting his finger to his already-opened temple. "Bang," he whispered.

"Bang," Sherlock repeated. "Four times. Four bullets. Four times you pulled the trigger."

"Bang," Victor repeated, and this time Sherlock heard the gunshot. Victor vanished as if smoke and Mycroft replaced him.

"Sherlock, can you hear me?" Mycroft seemed extremely concerned.

"Bang…" Sherlock's voice was the whisper now, staring beyond his brother's face, zoned out, heart pounding.

Sherlock heard Mycroft swear—presumably he saw the drugs on the table, left in plain sight. Stupid. Sherlock felt ill, doused in sweat as Mycroft felt the pulse in his neck and used his own mobile to dial for an ambulance. "Bang. Why?"

"Sherlock, hold on, stay with me. An ambulance is on its way." Mycroft was being unusually physical, stroking Sherlock's aching head. When the ambulance arrived, and Sherlock was loaded in, he couldn't think properly again.

"Why?"

The ambulance nurses looked at one another. "You've overdosed, Mr. Holmes."

"Why? Why did you do it?" Sherlock took a sharp breath inward.

"He's delirious."

The next few hours were an utter blur—a mix of lights and sounds and smells in the hospital. Mycroft's voice, talking to him as he lay weak and unable to breathe on his own. Antiseptic and plastic and once or twice, food. Doctors checking pupil response, moving him from the ER to another room, lights on the ceiling scrolling through his vision. He never did get to figure out what happened that made Victor snap. It was his first unsolved case, and one that hit far, far too close to home.