The door of 221B stood slightly ajar as John Watson made the familiar climb up the stairs, noting the stream of dim light from within. He rapped on the frame, waited, then tentatively pushed the door open.

The room was, to say the least, a wreck. Had John only been gone for a week? Everything from books to plates to socks had been left where it fell—on the floor, on the mantle, on John's chair. He wondered if poor Mrs. Hudson had seen this. He'd hate to see the look on her face when she did.

The door was caught on a wrinkled sheet, but John forced it open enough to enter the room, and there was Sherlock—sitting at the table, head bowed, unmistakably asleep. The only light in the room was from a table lamp and the glow of his laptop.

"Sherlock." John shook his friend's shoulder. "Sherlock—hey."

"Mm—" Sherlock woke up, blinking. He looked up. "What were you saying?"

"I didn't—Looks like you fell asleep."

"'Course I haven't. Why would I fall asleep in the middle of a case?" He turned his attention back to the computer screen. John saw he was scrolling through a forum thread titled I think DYMM could be ITV hoax?

"You're keeping busy with the investigation, then?"

"Yes, I—oh," he added self-consciously, looking at the mess as if he hadn't noticed. "Yes, I've been keeping busy. I can't remember the last time I had a case that demanded this much focus, it's so…" He stopped reading, looked up and, for the first time, seemed surprised to see John. "Sorry, what are you doing here?"

"I came by to give you this." John fished a flash drive out of his pocket and set it on the table. "It's your brother's. He says it's—"

"Mycroft sent this?"

"Yes, and he says it's all the files he has on Moriarty. This stuff goes back years, before you and I ever met him. He seemed to think it would help."

"'Course he did, no doubt he expects me to be grateful he's lending his expertise for a change…" But Sherlock plugged the flash drive into the laptop.

"And I had a word with him about the other thing …" John's eyes fell on a newspaper clipping on the table. A government vault broken into late last night, a message emblazoned across the windows in red paint: DID YOU MISS ME

Sherlock glanced at the clipping. "Certainly took them long enough. Sloppy work, if you ask me."

"How?"

"We know someone went to a lot of trouble to convince us they were Moriarty." He tapped the clipping. "This is not Moriarty—and even if it were, he wouldn't bother putting his name to it. He was never in it for the money; that wasn't his style."

And you would know, John thought, but he could tell this wasn't the time. "Right. It's been a week—what else have you got?"

"Nothing."

"Nothing?"

"Well—information. Disparate. I don't know what it means—not yet." Sherlock nodded to the opposite wall. John saw he'd hung up a map dotted with pins and a few newspaper clippings, mostly related to the front-page news that had started it all: Moriarty's reappearance.

John looked closely at the map. "Nothing's connected," he observed.

"Every screen in the country. Not much of a pattern."

"A heat map wouldn't tell you anything."

"Right."

Then John realized there was one story that hadn't made it to the wall yet. "What about this vault thing? I mean, do you think it was the same person?"

"It makes sense if it is. I had a word with Lestrade. The level of security and the ease with which it was breached suggests an inside job, so they're questioning people who knew the passcodes and alarm information. Problem is, there's no one person who had all the information you would have needed to break in. Which suggests that someone knew his way around all those people. And someone would have had to know their way around a lot of people to make that happen in one week." He stabbed a finger at the wall without looking up. "We know Moriarty could get to people. People are easy if you know what you're doing."

"But you don't think it was Moriarty."

"No. Like I said, he would have the means and not the motive, unless he needed the money for some reason, to pay someone off maybe, in which case..." He trailed off.

John was about to excuse himself when something occurred to him. "What do you mean, 'one week'?"

"Hm?"

"You said the person who did the screens only had a week. What makes you think they were only working on it for—?"

"Since I killed Magnussen, yes."

John unshouldered his coat. "Why?"

Sherlock looked at him blankly. "Why what?"

John sighed. "Just back up. Why do you think they've only been working on it since Magnussen died?"

"I know they've only been working on it since then because my brother called me four minutes into my exile to Eastern Europe and told me my greatest enemy was back from the dead. Think about it, John."

"You're saying this wasn't a coincidence?"

"Four minutes after the plane took off? Do you think it was?"

"So whoever did this was trying to bring you back?"

"They would have had a week to prepare, which could be enough time if they had the right connections in place already, so we're looking for someone in a position of power, the power to put Moriarty's face on every screen in the country, and they used that power to stop my exile. Why? Who'd go to all that trouble to help me?"

"I can think of a few people."

Sherlock typed a reply to the thread, then sighed, exasperated. "Moriarty, John, back from the dead. Do you know many people who could have done that? Well, of course," he added reflectively, "it would have taken nothing less, what with me being a murderer and all."

"Sherlock, you're not—"

"Don't." Sherlock didn't lift his gaze from the laptop.

John tried again. "Sherlock, you did what had to be done, okay?" He watched him for a response and got none. "All right, Magnussen was going to…destroy us, and Mary, so really it was—"

"It was murder, John; it was an assassination. If it had to be done then why didn't you do it?" He keyed in a URL and punched the Enter key a little too violently. "You were closer to him; I'm sure you could have killed him faster and with a lot less melodrama."

"I didn't think…" John trailed off, but he could see Sherlock wasn't expecting a response, so he stayed watching him. It occurred to him how strange his friend looked—his eyes darting back and forth, the white glow of the laptop washing the color from his face, the tabletop an island of light in the cluttered space they'd once shared.

"Does it bother you?

"Hm?" Sherlock continued reading.

"You're saying whoever did all this stopped your exile, saved your life. Does that bother you?"

"Should it?"

And here comes the tricky part, John thought with some irritation, because the trouble with Sherlock was that for someone who enjoyed the sound of his own voice that much, if he didn't want to talk about something, he wasn't going to talk about it nine times out of ten. But because he was starting to worry and because he didn't have anything better to do, John decided to bank on the one.

"Well, they committed an act of terrorism. Probably the vault robbery too. And now you want to put them behind bars? The person who saved your life?"

Sherlock was typing something. He didn't look up.

"Or are you not worried about that right now?"

After a few more keystrokes, Sherlock's fingers came to a rest. He stared into the screen for a moment, then stood up. "All right."

John stepped over a few chess pieces before moving the clutter from his chair. He took a seat, and Sherlock did the same.

Sherlock clasped his hands in front of his face. "It's no use. I need a second opinion."

"What about?"

"Our supposed Moriarty, the person who did all this, just—You know as much as I do. What can you tell me about them? Anything you've got."

"Well, like you said, it's someone powerful. And someone who wants to protect you, for some reason."

"Yes, and…?" he said impatiently.

"And someone who's not bound by…" John shrugged. "Conventional morality?"

"Conventional morality?" Sherlock laughed. "I thought moral people called that 'morality.'"

"They did it to protect you; I don't think they—" John struggled a moment with the words "—did the wrong thing, necessarily."

Sherlock's eyes flashed up. "It was justified, then? You think so?"

"I think so, yeah." It was the truth, but John didn't know whether it was the answer Sherlock wanted. He couldn't imagine where this was going.

"And what happens next? If people start getting hurt, is it still going to be worth me being back?"

"We'll solve it. We always do—"

"If people die, is it going to be worth it?"

Now John was really worried. It wasn't like Sherlock to ask these kinds of what-if questions. Surely the self-styled sociopath wouldn't waste time worrying about whether he ought to be happy that Moriarty was back.

Even John hadn't spent too much time on it, but there was a reason for that. He knew he was glad Sherlock was back safe—whatever else happened. He knew, selfishly, that it wasn't (as he'd pretended to himself for a bit) because of the balance of good that Sherlock was capable of given a long and happy life. No, that wasn't why he was glad his friend had survived. But Sherlock had just asked a question John had stopped short of answering to himself. And he didn't want to answer it now.

"Sherlock, what do you want me to say?"

Sherlock stood abruptly and turned back to the computer. "Actually, you know what? Never mind."

"Sherlock—"

"I don't want you to say anything." Sherlock pulled up a chair and sat back down. "It was a question, and if you don't want to answer it that's fine, but then you should probably leave me to my work."

"Right." John stood up and pulled his coat back on. "I'll just leave then, why wouldn't I, I've only left Mary at home…I was only trying to help."

"I appreciate you trying," Sherlock said coldly.

John tried to ignore this remark as he took one last look at the pins on the wall. As he did, his gaze fell on something he hadn't noticed before: a clipping pinned awkwardly, the pushpin jammed into the wall at an angle, forcefully, reflecting a moment of frustration…

Something's not right, John thought as he turned back to look at Sherlock, who was once again absorbed in the laptop screen, dead to the world was how it seemed. And John knew Sherlock would eventually come around and would let John help him with the case, but there would be no talking to him tonight, not when he'd decided that he didn't need any help, and John knew he should just walk out without another word, but something wasn't right and he had to say something even if it wouldn't make any difference because making a difference wasn't the point.

"Sherlock…When…and if—you decide you want my help…just let me know, all right?"

Sherlock inhaled sharply, and John prepared himself for the parting shot he knew was coming, but it didn't come. Sherlock didn't look up from the computer, but something changed in his eyes, and John had the unaccountable thought that his friend was about to tell him something important.

What he said was, "I will."