He woke up and found himself in a corridor he usually – well, not avoided, but tended to ignore. It was the one who held his memories of the two years spent away from London.

In the next moment, he sprang up when he realized that he hadn't entered the palace voluntarily. He tried to leave, but to no avail, and knew what had happened.

Moriarty had taken control again. He must have grown bored waiting for Sherlock to make the next move. And this time, he didn't know what was going on in the outside world. He couldn't see or hear anything. Because he had not found the paths Moriarty used – he hadn't yet had the time to look for them, and before, looking for a connection to his senses had been perfectly useless since he had never believed that he would one day be locked in his mind palace – all he could do was go to the place they were most likely to be.

Since he had cleaned and reorganized his mind palace many times, he decided that he should look near the science corridor, namely biology. John had once called his knowledge in this respect "unsystematic", simply because he didn't include many topics the doctor had learned in medical school. He had never been interested in how to save a life, other than treating small wounds or recovery position, nor in simple illnesses; he had been fascinated by anything he considered useful for his work.

Necessarily, after having stumbled upon a case where the killer had gouged the victim's eyes out, he had collected every information about the organ. If there was a link to his eyes somewhere, surely it would be near these rooms.

He deplored the state of the building as he hurried towards them. How he could have overlooked it was a riddle he wasn't sure his mind could have solved in its best state. He didn't even know how much he still had control over; Moriarty might have sent him here, having him believe that he needed to go to the science rooms, instead of where the path actually lay.

As of yet, he had no evidence that Moriarty could implant thoughts, he told himself angrily, and moved forward. The corridors had always been large, airy and light; while he had to walk down dark alleys frequently enough in the course of his life, he had no desire to do so in his own mind as well. The parts of it he could organize would always be bright and easily to navigate.

He seemed to meet shadows at every corner since he had noticed something was wrong. It didn't feel like the building he had started to design when Mycroft had taught him the technique in his youth (and as he remembered the sunny, warm day he suddenly found himself grateful that he had never been interested in his brother's work; Moriarty would have used it against him, London and the country if he could) anymore either. While he had never paid much attention to the atmosphere – it had always been pleasant, perhaps an unconscious adjustment during construction – never once had it been menacing or mysterious. He adored mysteries in his work. In his mind, he needed order. He needed clarity. Moriarty, of course, knew this and had first brought terror and nightmares to unsettle him, and it had stayed and changed his airy rooms and corridors into dark, clustered places in which he could barely see a few feet in front or back. Some seemed longer or shorter than he remembered as well.

The damage that had been done might be irreversible. Until now, he had not allowed himself to dwell on it. He recognized this as a weakness, naturally – he couldn't expect to beat Moriarty if he didn't include all factors in his assessment of the situation – but he had been focused on calming down, become rational again, and this topic would have made it difficult. Realizing there was no way around it when he saw the chaos Moriarty had caused, he pondered it with indifference. If he had to spend the rest of his life afraid of his own mind, whether he be victorious or not...

He knew what he would do then, what he had to do then. If he defeated Moriarty and realized his mental health was to upset, if he feared becoming what he had always felt he might have become if he had been a little more insane and a little less inclined to solving crimes instead of committing them, if he wasn't able to continue working, if his friends saw what he had turned into –

It would be time to draw the consequence. After he had won, Moriarty's programming must disappear with its creator, and even if it didn't, he would have enough time to do it himself before he brought everything to an end.

He might die one way or the other because of his stupidity of chaining the consulting criminal. The punishment fit the crime. It had been incredibly idiotic not to let him just live on his memories. He had been weak and scared.

No wonder Moriarty had chosen fear as his weapon, since it was what brought him into existence in the first place.

And yet –

How complete could Moriarty be? Sherlock had never learned anything about his origins, other than when he began to provide services to the criminals of London. Many aspects of his personality, of his experiences must be missing. What kind of creature was he? Did he notice his own shortcomings? Did he perhaps draw not only from Sherlock's memory of him, but of Sherlock himself? Sherlock had never doubted that he would have made a good criminal, even if in many respects – his role as a planner and supervisor, rarely venturing out except when he decided that none of his employees could be trusted – Moriarty resembled Mycroft more than he did Sherlock, although he probably had never recognized this. If this Moriarty could harness the darker aspects of his personality, it would make him stronger and more unpredictable, since no man could ever claim to truly know himself. There was too much hidden in the shadows of the mind to ever see completely clearly. It was one of the reasons Sherlock had continued building his mind palace to begin with. To have some semblance of structure.

In his other cases, he could look at the evidence and follow clues, leaving him little time to theorize. In this one, fighting within his head, he could do little but. It distracted him from pushing forward. At least he had reached the science corridor now. It had taken long, far too long; even his movements had become restricted since Moriarty had escaped. Maybe he had changed the outline of the palace – but he would have noticed that; no, it must have to do with the fear he was continually experiencing, the shadows that made it difficult to see and find his usual sag ways. One of the disadvantages of structuring his mind – the only disadvantage until the consulting criminal – was that he couldn't jump from room to room unless he built a connection first. Otherwise the whole exercise would have been fruitless. Normal people jumped from memory to memory, from association to association, from detail to detail without noticing that they did or why they did and in the process lost much of the abilities every mind had. To bring order into the chaos meant to let go of a certain part of spontaneity – and he was aware that John would have laughed, had he expressed the sentiment – but it made it easier to use the power of his brain. So he had to walk from room to room if he hadn't made sure that he could jump to certain others first. It had never bothered him, and he was determined that it shouldn't even in this situation. At least Moriarty had not landed in a mind already as chaotic as the minds of average people; it would have been easier to turn him insane.

The room on the eyes – he wrenched the door open. There had to be something here. There had to be.

Moriarty could not have spent much time here. It was still clean and light, and Sherlock sighed with relief. He closed his eyes and began to search; something, a glimmer of a connection he had never established but that must be there because the sensory organs had to communicate with the mind –

And suddenly he could see and hear himself speak as he told John about a case he had not solved but Moriarty had while he had been unconscious.

The rage he felt as his best friend looked at the consulting criminal like he always looked at him because he thought he was him made it easy to win this time. He forced himself forward and was in control with his body.

Thankfully, Moriarty, who was once more in an undetermined location in his mind palace, had just finished the story and John didn't question his lapse into silence. He was used to it.