A/N: Sorry for the long wait for this update. I couldn't figure out how to introduce all of this new plot, but I figured it out.

Warning for graphic-ish murder. There's blood. It's not much.

Also, for a 'previously on', because you might need a refresher, this chapter has a bit to do with chapters 3 and 48-49. It mentions things that were mentioned first in those chapters.

Please review!

Sherlock is so excited to go to Lestrade's office the next morning that he's up before Mycroft gets there. Clement comments that he's up before he is for school every day, and Sherlock just waves him off while pouring his coffee.

Mycroft finally arrives and they get to Lestrade's office a bit after eight o'clock.

"Wow," Greg says as they approach his desk. "I didn't think you'd be here so soon."

"Someone was too eager to be patient for any longer," Mycroft tells him.

Greg leans in to kiss Mycroft's cheek, then he pats Sherlock's shoulder and leads him over to a separate desk.

"So," Greg says as he pulls up a chair for Sherlock. "Here's what we have. It's a murder, just a regular drug deal gone wrong."

Sherlock picks up the file, a bit disappointed. This doesn't sound as difficult as he thought it would. "So…you need me because—" He opens the file and realizes why Lestrade needed him.

His stomach drops when he sees the victim. "Danny."

"He wouldn't gotten mixed up in that if he wouldn't have made bail." Lestrade shakes his head. "We could've—"

"Hey," Mycroft stops him. "He was in bad things, Greg. You couldn't have stopped it."

Greg nods. "Anyway, Sherlock. I need you to find the guy who did it."

"You can't?" Sherlock asks, a bit defensive. He didn't really know Danny, and Danny was a bad guy, he hates Danny for what he did to Taylor, but he still can't help but feel like Danny's life should have been spared. At least for the sake of the love Taylor still has for him.

"We can't," Lestrade admits. "Look, Sherlock, if…if you can't, we understand. I know you actually have something to do with this, so if it's too hard, then just go home, okay? It's alright."

Sherlock shakes his head. "No. I want to. I can do this."

"Good," Lestrade says. "We'll leave you to it, then."

Sherlock feels Mycroft kiss the top of his head, then the two men leave.

Sherlock gets to work right away, starting with the crime scene photos. He looks at the pictures of Danny's body, seeing that he was stabbed six times. Blood is everywhere, it's splattered all over the walls, there's a puddle around his body, his clothes are soaked, it's coming out of his mouth, and Sherlock's stomach turns unexpectedly.

He runs to the bathroom and regrets actually eating breakfast that morning. His stomach is empty in minutes and there's a bang on the stall door.

"Sherlock?" Lestrade calls. "You okay, mate?"

Sherlock flushes the toilet and opens the door.

"Boy, go home," Lestrade says. "I'll take care of it."

"No, no. I can do this." Sherlock steps past him to wash his face and rinse his mouth out.

Lestrade gives him a piece of gum. "Are you sure?"

Sherlock takes it and nods. "Just give me a minute."

Lestrade leaves him in the bathroom.

Sherlock checks the time, finding that it's 8:30 and that school started only thirty minutes ago. He calls Olive anyway.

She answers on the last ring. "Hey, what's up?"

"Nothing, I just…" he stops, remembering that he can't tell anyone what he's doing. "I just…I'm checking up on things."

Olive laughs. "Things are fine."

"How's everyone?"

"Everyone's fine…" Olive says. "I saw John flirting with a cute red head this morning, but he's totally not her type—"

Sherlock ignores her. "How's Taylor?"

Olive laughs again. "Taylor? Taylor's fine, why?"

"No reason," Sherlock says.

"Yeah, right. What is it, what's going on?"

"Nothing. I…if I can I'll tell you later. Just keep an eye on her, okay?"

"Okay…Sherlock, what's—"

Sherlock hears someone coming into the bathroom. "I have to go. See you later."

"Sherlock, wa—"

Sherlock hangs up quickly. He smiles weakly at the officer entering, then rushes out of the room.

His stomach settles enough to start again. This time, he doesn't have any interruptions. His phone does go off with text after text from Olive and Mycroft, both asking if he's okay, but Sherlock puts his phone in a desk drawer and ignores it. He figures if anyone really needs him, like his dad or brother, they know to call Lestrade.

He works all day, going through every note over and over again. There were no fingerprints found, no weapon, and Danny's body had been there for hours before he was found, giving the murderer enough time to toss the knife.

Danny's body was discovered by another friend of his named Jack, but Jack had an alibi. Sherlock remembers Taylor said another friend of Danny's was named Kai. And then there's the guy he saw outside the house when they followed Danny.

He looks through the notes, finding the transcript of Jack's interrogation. He mentions a Kai, but there's nothing more mentioned about Kai.

Sherlock gets up to go to Lestrade.

"What's up, 'Lock?"

"Don't call me that," Sherlock says. "Was there any follow-up about that Kai person that Jack mentioned?"

Lestrade motions for Sherlock to sit at the seat next to his desk and leans forward on his elbows.

"That was the thing about Kai," Lestrade says. "Jack gave us the name Kai Jameson, but Kai Jameson was a…" Lestrade frowns. "Well…this Kai stole the identity. Kai Jameson doesn't exist. Anymore."

Sherlock furrows his eyebrows. "But…"

"We can't find him. Sure, he might be the killer, but he's nowhere to be found."

"Who owned that house?"

"It was bank owned, I guess. Nobody lived there. They all just met there to shoot up."

Sherlock bites his lip. "We need to find that guy," he says.

Lestrade nods in agreement.

Sherlock takes a lunch break because Lestrade is making him, so he goes down to the street to sit at a bench for a while. He takes his phone with him, and he finds that there's a dozen messages.

Most of them are from Olive. The last says, 'Danny is dead isn't he?'.

Sherlock decides to call her.

"Hello?" she answers almost instantly.

"Hey."

"Was my deduction correct?"

"How'd you get to it?"

"The only thing I could think of that Taylor would have that the rest of us don't: Danny. You asked if she's okay, so I figured either he was after her or something happened to him. She's perfectly fine, so I knew she wasn't in any danger."

"Nice," Sherlock says.

"You don't sound very good."

"Well," Sherlock says, "I just can't find his killer."

"You will," Olive says.

"I don't know. This doesn't match any other drug or gang related murder that's occurred lately. It was done with a knife, so that means the killer wasn't very experienced as a killer. And now there's someone running around with a stolen identity that could very well be the killer."

"Wow," Taylor says.

"Yeah. I just…I hated Danny, but I still want to find his killer."

"I know you do."

Sherlock sighs. "I'll let you get back to school."

"Alright. Call me later."

"I will. Goodbye."

Olive says goodbye back, then Sherlock hangs up to go back inside.

Jack had said in his interview that only he and Danny knew Kai, and that nobody else had been to the house in months. For at least four months it was only himself, Danny, and Kai, and not even he knew where Kai was during the time of the murder. Jack confesses that Kai is probably the killer, for he and Danny started to fight quite a but towards the end. There was evidence that there was a fist fight before the stabbing, and Jack says that sounds like Danny and Kai.

Sherlock is put at a loss. There's no Kai, he doesn't exist, and they may never find him.

After going everything again, he gives up around three o'clock.

"I'm going home," he says as he approaches Lestrade's desk.

Lestrade sits back in his chair. "Callin' it a day?"

Sherlock shakes his head. "I can't do it. I'm sorry."

Lestrade stands and motions for him to walk away from the desk towards the elevators. "Don't beat yourself up, okay? Lots of experienced detectives can't figure it out. This guy...he's good, I guess. Maybe not good at murder, but good at staying out of the world when he needs to."

Sherlock presses the down button on the elevator.

Lestrade continues. "Go home. Enjoy your brother because I'm stuck here a while longer and I can't."

Sherlock absentmindedly nods.

"Hey," Lestrade says.

Sherlock looks up.

"Relax. I'll find you something else when I can, alright?"

Sherlock nods.

Lestrade pats his shoulder, then the elevator arrives and Sherlock leaves.

Sherlock gets a cab home, and when he gets there John is waiting with Mycroft.

"Didn't solve it?" Mycroft says, more of a statement instead of a question.

Sherlock shakes his head.

John takes him in a tight hug. "It's alright, love."

"Mmm," Sherlock replies.

Mycroft ruffles his hair. "Go up and take a nap. I'll wake you for dinner."

Sherlock nods, then he and John go upstairs for a nap.

Nobody brings up the case again, but Sherlock doesn't stop thinking about it. He wants more of an opportunity to find Kai, but he knows the man is a ghost a will probably never be found.

The next day, Friday, Sherlock lets Mycroft take him to the museum of art to take his mind off things and focus his frustration on the fact that he's at an art museum. It works, because after he's there for an hour he begins to gripe about it instead of moping about the case.

Mycroft just grins the rest of the way through the museum and Sherlock whines at every exhibit.

John reminds Sherlock of his party later that day when he calls Sherlock on his lunch break.

Sherlock whines. "Do I have to go?"

"You don't have to, but I really want you to."

Sherlock groans. "Fine. But I'm bringing Olive."

"I already invited her."

"Good. Guess we're on the same page, then."

John laughs. "Whatever makes you happy, babe."

"I'd be happy if I could stay at home." He looks at Mycroft. "I'm sure my brother has plans for me—"

"I do not," Mycroft says.

Sherlock groans again.

"It'll be fun!" John tries.

"Fine, fine."

"Great," John says; Sherlock can hear his smile. "I've got to go. I love you. Come over around five."

"Fine!"

"I love you!"

"I love you too," Sherlock mutters.

John laughs. "Bye, love."

"Goodbye," Sherlock says, then he hangs up.

"It wouldn't kill you to spend time with your friends."

"I would hang out with them if it was at my own home without a party involved."

"Dad said you barricade yourself in your room when your friends are at our house."

"Yeah, but they're still there, aren't they?"

Mycroft rolls his eyes.

"It's not like you had friends when you were my age," Sherlock says.

"And now I do have friends. See how the world works?"

"You don't have friends, you have me and Lestrade."

Mycroft wraps his arm around Sherlock's shoulders and squeezes him. "And aren't we the best of friends?"

Sherlock makes a noise and shoves him away. "Get off!"

Mycroft laughs and leads Sherlock further into the museum.

He shows up to John's at five, as promised. Like with the party a few months ago, he and John sit on the sofa and talk before guests arrive.

Harry gets home with the party supplies (lots of alcohol) about an hour later. They help her and Clara set everything up, then Harry and Clara disappear upstairs to get ready.

Olive is the first guest to arrive around seven. Sherlock is very happy she's there, because soon after, other guests begin to arrive and John gets mixed up with everyone else instead of them.

Sherlock and Olive sit on the sofa for most of the evening, until a few people sit around them and two couples begin making out. Then, they move to sit on the stairs to act as a buffer to upstairs.

"John looks happy," Olive observes.

Sherlock looks over to him. "Oh, yes. He enjoys this type of thing."

"I can tell," Olive says.

"Last time, Harry's girlfriend kissed him. That wasn't very good."

"No, I would think not."

Sherlock looks over at her and notices she's not really focusing on anything in particular. Her eyes are darting everywhere and she sips her drink every few seconds, then immediately makes a face after.

Sherlock sighs. "If you're going to be here with me, the least you could do is stay sober, too."

She looks at him. "Hmm?"

Sherlock shakes his head. "Nothing."

Olive grins widely at him. "Oh, lighten up. Free booze!"

Sherlock rolls his eyes.

She wraps her arm around his neck and rests her head on his shoulder.

Sherlock leaves her. "Where is Lane?"

"I don't know," she says. "I miss him."

"Do you?"

"Yes!"

"Mmm," is all Sherlock says.

Paris approaches them a minute later. "There you two are. John said you were on the sofa, so I went over and there and got stuck talking to a girl for twenty minutes."

"Was she pretty?" Olive asks, sounding jealous.

Sherlock looks at her, wanting to cut her off and take her upstairs to sleep, but before he can, she stands and takes Paris's arm.

"Let's dance!"

Paris laughs and smiles. "Alright," he says, taking Olive into the living room where music is playing loudly.

Sherlock stays on the stairs, just watching everyone around him. He feels better out of the action, being able to watch without being watched. Nobody is paying attention to him.

A while later, Sherlock begins to feel tired, so he stands to go upstairs. When his back is turned, he hears someone down a few steps behind him.

"Hey, Holmes," a deep voice says. "I've been looking for you everywhere."

It's not anyone Sherlock recognizes, none of his friends, but he turns around to see who it is anyway.

His stomach drops immediately. That face, he recognizes it. He falls back against the wall and the boy walks up the few steps to stand closer to him.

Sherlock's stuck in shock where he is.

It's him, Sherlock thinks to himself. The guy who was outside of the drug house. It's Kai. It's him.

"Ben," Sherlock mutters.

Ben smiles widely. "Good to see you, mate. Especially since our time last party was cut short."

Sherlock clears his throat. "I, uh—"

"How's it going? Solve any good cases lately?"

Sherlock furrows his eyebrows. "How—"

"Your boyfriend really won't ever shut up about you. The entire ride to their grandmother's house, he sang like a bird about how amazing you and your case solving business is."

Sherlock doesn't say anything, he just swallows in fear.

"We need to talk, Sherlock."

"About what?" Sherlock chokes out.

Ben looks around. "Too many people here. I'll call you."

"Don't."

Ben steps up to him, more in Sherlock's face. "You really don't want to try to tell me what to do," he says.

Sherlock swallows again. He feels so nervous that he wants to throw up. Images of what he did to Danny swirls in his head and he can't breath, not with Danny's murderer so close to him. He wonders how many more there have been.

"I have to go," Sherlock quietly says.

"Don't bother," Ben says. "I was just leaving. I only came to say hello." He takes a step back.

Sherlock takes a deep breath.

"See you later, Holmes," Ben says.

Sherlock doesn't say anything, he just stands there and watches from his post as Ben leaves the house a minute later.

When he can gather his thoughts and press off the wall, he rushes down the stairs to the kitchen. He needs to relax, so he gets a plastic shot glass from the stack and slowly pours himself a shot of the first bottle he grabs. His hands are shaking uncontrollably, so sticky liquid gets all over his fingers, but he drinks the shot and actually tries not to cry.

He pours himself another shot.

"Hey hey," Olive says next to him. "Slow down, you're going to make yourself sick! That's straight cherry flavoring! It's pure sugar!" She laughs loudly.

Sherlock looks at her.

"Wow, wow," she says. "What's wrong?"

Sherlock feels a tear fall. He can't stop himself from crying, and still shaking. Olive cups his face and wipes under his eyes with his thumbs.

"What's wrong?" she repeats.

"I…I…" Sherlock can't bring himself to talk.

"Take a deep breath, relax."

Sherlock sucks in a quick, harsh breath through his mouth, but lets it out quickly. He does it over and over again, and he starts to panic because he recognizes that he's going to hyperventilate.

"Sherlock!" Olive cries.

She clearly doesn't know what to do either, so she presses her lips against Sherlock's. Sherlock stares into her eyes and this time takes a deep breath through his nose. She pulls back to let him breathe out.

"Calm down," she says, "Slow breaths. Just like that."

Sherlock breathes slowly and feels his body relax. His hands slowly stop shaking and he can finally gather his thoughts.

"I'm sorry for kissing you," Olive says. "It was that or slapping you, and I felt worse about slapping you. It would have been more fun, but."

Sherlock smiles weakly.

Olive rubs his shoulder. "Now, what happened? What's wrong?"

Sherlock rubs a hand over his face. "I…I just…"

"Take your time."

Sherlock looks around. "Not here. Come on."

He takes her hand and leads her upstairs to John's bedroom.

They sit next to each other on the bed and Sherlock rubs his face over and over.

"What happened?"

"Did you see that guy who was talking to me on the stairs?"

Olive nods. "Yeah. Why?"

Sherlock rubs his eyes. "That was him, Danny's killer."

"What?!"

"He has a different identity. Lestrade says he stole the identity he had been using for drugs, I guess. But he's the guy I saw outside of the house we followed Danny to. It's got to be him, he's got to be Kai. He killed Danny."

"Sherlock, that's a big accusation. How do you know? How are you sure?"

"I just am," Sherlock says.

"What did he say to you?"

"He must know somehow that Lestrade called me for the case. He said we need to talk. He said he's going to call me."

"Do you want to tell Lestrade?"

Sherlock shakes his head. "No. Lestrade isn't going to believe me."

"How do you know?"

"Because you don't."

"I didn't say—"

"I can tell that you don't."

Olive pinches the bridge of her nose. "Sherlock, it's just…this is a huge thing. What are the odds Danny's killer comes to this party?"

"This isn't a coincidence. The universe is rarely so lazy."

"What does that even mean?"

"He mentioned the cases I do at school."

"So?"

"Maybe he's involved in those."

Olive sighs. "Sherlock, your imagination is getting the best of you."

"No," he disagrees. "I know. He's not Ben, he's…he's involved in all of this somehow."

Olive shakes her head. She pats his shoulder. "Just be careful. If he is who you think he is, then he's capable of more than anything to do with the cases you've solved at school."

"I know."

Olive stands, then just as quickly sits. "I'm still a bit drunk."

"Clearly," he says. "Here, lay back. Sleep here."

"No, I…I'll go home, I—"

Sherlock takes her shoes off and places them on the floor. "Just go to sleep, okay?"

Olive nods. "Thank you."

Sherlock turns the light off, then exits the room.

He returns downstairs to find John to tell him he's going home, but John begs him to spend the night. Sherlock decides he wants to stay with John because he's too afraid to walk home and he also just wants to be comforted after everything he's gone through this evening.

They let Duke sleep in John's bed with Olive, so they sleep on the floor on an air mattress.

"Thanks for staying with me," John whispers in the dark.

Sherlock snuggles closer to John. "I really needed to tonight."

"Why? Are you okay?"

Sherlock knows John is still drunk, so he decides to save this discussion for the morning. "Yeah. I'm fine. I just missed you the past two days."

"I missed you too, babe."

Sherlock kisses John lightly. "I love you," he whispers.

"I love you too. So much."

Sherlock holds John tighter and buries his face in John's chest. "So much," he repeats, closing his eyes and welcoming much wanted sleep.