"She was pretty." John didn't mean anything by it other than an observation.

"I didn't notice," Sherlock said, suddenly no longer relaxed.

"It was just a comment."

"She would no doubt be interested in dating you."

John knew then he should change the subject. "Is there really a way to put something on a flash drive but not make it visible to anyone?"

"Obviously not so no one can ever see it, but there may be some specific function that needs to be performed to access the data. There was a case where a website only gave hidden content when a specific access sequence was followed..." Sherlock abruptly stopped, blinked, swallowed, and then went on. "He may have not remembered to share that with his daughter. Or he deliberately kept it from her so she could be shielded by never knowing what was on it."

"Not that that's going to make much difference now."

"It depends on whether the people who want to keep this information secret know she has it or not."

"Do they even know it exists? From the way they stopped going after her father, I'd guess they didn't think he had anything of note."

"Or that circumstances would make it impossible for him to share the information with others."

"Blackmail?"

"Perhaps." Sherlock shut his eyes, lay down on the sofa, and put his hands together. He was obviously thinking about the case, so John knew he didn't need to try to get him out of it.

A terrible thought occurred to him. Sherlock had warned him that he could go for days not speaking. Was he really just lost in his own thoughts, or were those occasions where he was having a flashback or disassociating? He remembered times where Sherlock would ask him to do something as soon as he got in the door. At first John had assumed he was just so lost in his thoughts that he hadn't been paying attention to the fact John had left, but if he had been in one of those states he genuinely might have not been aware that time had passed. He shivered and headed to the kitchen to make a cup of tea.

As soon as he put the water on to boil, Sherlock spoke again. "There's potentially an infinite number of configurations that may have to be done before the drive could yield information."

"Needle in a haystack." John knew even Sherlock couldn't work that many different possibilities.

"However, the drive has those initials. Presumably they give a clue to how to access it."

"Four steps, then." John felt his mobile vibrate in his pocket. Since the kettle had boiled, he went back into the kitchen and pulled it out once he had his back to Sherlock. It was a text message from Mycroft, of all people.

"I will speak with you tomorrow." Even though he hadn't elaborated, John suspected he knew what he wanted to discuss. He put the phone in his pocket, poured himself some tea, and went back into the sitting room like nothing was amiss.

"Longitude and latitude!" Sherlock pulled out his own mobile and began to type furiously. "John, put the flash drive in your laptop and pull it up in the main computer. Then enter N 27 E 78."

He picked up his computer from the floor, booted it up, and once it was started inserted the flash drive. Nothing happened, so he went to the drive directory and entered the sequence. Once again, nothing happened. Not even an error message. "I got nothing."

Sherlock didn't seem bothered by this. "How is Agra written in Hindi?"

"Don't you need a particular type of font to see something like that?"

"We can install it." He turned back to his mobile. "Give me my laptop."

"It's right by you on the floor."

Sherlock let out a loud sigh and picked the laptop up. "I want to see the year when the city of Agra was founded."

John was suddenly reminded of Irene Adler's old phone. "Maybe we should just enter 'Agra' all on its own?"

"Try it. It can't hurt."

He typed it in. "Still nothing." John looked down at the drive again. "Wait. Since there's eight digits there counting the dots, maybe it's an eight digit code?"

"Unlikely."

"But the longitude and latitude were six, if you count the directionals."

It was clear this had just occurred to Sherlock; he suddenly looked curious. "True. Just try the numbers, then."

"What were they?"

"27 78."

He typed in the numbers all by themselves. "Still nothing."

Sherlock made a noise of acknowledgement. "Agra doesn't appear to have a formal date of foundation. It was first mentioned in 1080."

John didn't need to be directed to try it. "Nothing again."

"Give the drive to me," said Sherlock with a sigh. "I'll try the Hindi script." John pulled it out and handed it over. Sherlock plugged it in and furiously typed away. As soon as the keys stopped clacking the laptop beeped.

"Did it work?"

Sherlock shook his head. "No. I got a message that said 'An unknown error occured.'"

"Well, that's more than we got before. Check to see if it's got something on it now."

"I was going to do that." John came to stand behind Sherlock as he looked on the computer. The drive still showed as empty. Sherlock closed his eyes in thought. "Maybe he used his daughter's name." He typed it in and the computer beeped again, giving the same message about the unknown error.

John was out of ideas at this point. "I can't think of anything else."

"Mycroft is talking to you tomorrow," Sherlock said, like this naturally came from what they had been doing before.

"Yes." John knew it was pointless to lie about it. "Do you think we should talk to Mrs. Forrester?" The more Sherlock was focused on the case, the better.

"It would be helpful."

"Do you think her husband was a spy too?"

"I would go so far to say that not only was he a spy as well he was most likely killed because he was looking into this case. That is probably why her father was so desperate to save the information." He closed the laptop. "Trying to get into the flash drive now is having no effect. We should look into other parts of the case."

Secretly glad for the "we," John nodded. "Like what?"

"I want to look online and to see if there is any available information on Mr. Morstan or Mr. Forrester. I also want to connect any stories from either India or the UK at significant times in their lives."

If they had both really been spies, Mycroft would have undoubtably known more about them, and he was the logical person to contact. John knew better than to bring this up. "Anything else?"

"At this point, no." He opened the laptop again, took out the flash drive and put it aside, and his hands started to fly across the keyboard. It was almost like he had forgotten John was there, and uncertain what to do himself, John simply left the room.

Until that night, they didn't interact much. John and Mrs. Hudson watched a Bond movie together, and Sherlock passed on any dinner. Even when they went to bed he was silent. It seemed like a penny was about to drop. And of course one did.

John wasn't sure what woke him up. But it didn't take him long to figure out Sherlock was in the grip of one of his nightmares. He looked over at him and saw his eyes were open in a glazed, unfocused way. He was moaning softly. Unlike on some of those worse occasions, he wasn't actually saying anything. (Some of those one-sided conversations to K still gave John the shivers; not for what he knew, but what he didn't know.) The telltale sign, though, was that he had relenquished his grip on Hamish. Unless he was having a nightmare, Sherlock wouldn't let go of the bee until he was out of bed.

"Sherlock?" he said quietly. If he could wake him up before it got too bad he might just fall back asleep and not even remember that he'd had a dream. (He hoped that was the case and that Sherlock wasn't just choosing to push it out of his head.) He switched on a bedside light.

"Mike?" He sounded like a small child.

"John."

"Why don't you come and get me?"

This wasn't like any nightmare he'd dealt with before, and he had no idea how to deal with it. "You're safe here."

"It hurts, Mike." A tear actually came down from one of his eyes. "Can't you be my friend?"

It only then occurred to John who Mike was. "Your brother is there if you need him, now."

"She won't let me have you when we sleep."

"You have me right here and I'll be here whenever you need me."

Sherlock's arm brushed against Hamish and his eyes lost that glazed look. "What?" he muttered, his voice still thick with sleep.

"You were having a nightmare."

"Dream."

Just like Sherlock to not admit to something like that. "Whatever it was, you seemed pretty upset." He deliberately didn't mention what he had said in the throes of the nightmare.

"I'm fine now." Sherlock took Hamish back into his arms, turned off the light, and went back into his usual position on his side with the stuffed bee as a shield against contact.

John felt like he'd had a trip to a parallel universe. He suddenly couldn't wait to talk to Mycroft the next day.