"Never trust a con man." That had been what he'd told Watson at the start of their latest case. She had been baffled at the advice, which let Sherlock know that she hadn't known too many con men in her life.
"Isn't that a little obvious? That's like saying, 'don't get in the water if you can't swim'," Watson had eventually asked as they walked down the street.
Sherlock had adjusted his scarf and pondered the analogy. "No, it's more like saying, 'don't get in the water if you don't wish to be wet'," he adapted. "Do you know what 'con' is short for in the phrase 'con man'?"
"Confidence," Watson had answered.
"Precisely," Sherlock had said. "And the person we're looking for isn't just any con man on a park bench with a deck of cards asking you to 'follow the lady'. No. This con man, or woman, is exceptional at what they do. The victims seemingly abandon any common sense in order to follow this con man out into the night and away from anyone who can hear them call for help. The public knows there is a killer on the loose, the news broadcasts have made certain of it, and yet three victims in a single week. Each went with the con man of their own volition from a crowded street without raising any alarm. Whatever trick or scam the con man is using, it's good. Very good."
"Well, clearly they don't realize the person they're following is a con man. They wouldn't go with him if they did," Watson had pointed out, her attention wandering briefly to a card game being played in an alleyway.
"They don't realize until it is too late. There was no indication of a struggle on five out of the seven victims, which means the ploy is effective through the very end. The question is what is the scheme, what is the trick, that this con man is using. When we know that, we'll know who we're looking for." Sherlock had stepped to the side, his back soaking in the chill of the building he was pressed against.
Watson had taken a moment before realizing he wasn't at her side any longer and ducked back through the flow of people to return to him. "What are we doing?"
"We're watching," Sherlock had said, his quick mind already lost to the details in the crowd of people as he searched for answers in the minutiae of the way people called to each other and the patterns of their footfalls. Watson may have spoken to him again, he wasn't certain, but within an hour he had his answer.
There were no caveats, no exceptions, just two simple words that made everything so much simpler when they were applied correctly. Of course, it wasn't so simple. People trust chefs and waitstaff not to poison them. People trust that traffic will stop at red lights. People trust that their neighbor, their landlord, their loved ones, won't wake in a homicidal rage in the dark of night. Sherlock was all too abhorrently aware that the statement that 'no man is an island' was factual and that by simply breathing in and out he was trusting that the pollutants released by factories weren't going to kill him yet.
But the rule was really made for people on an individual basis. Sherlock supposed he could trust that the waitstaff at any given restaurant, on any given day, but there were was always a hesitation when he accepted a drink from someone he hadn't paid specifically to make and bring him that drink. Even Watson, though he'd pushed his hesitation down to a heartbeat because the last thing he needed was her latching onto the idea that he was paranoid. Sherlock wasn't paranoid; he was realistic. Fatalistic, even, though fate wasn't a concept that he was entirely comfortable with. Probability, the fact that certain things were almost bound to happen simply by the laws of the universe, that he could accept more easily.
For the first few weeks Watson had done well. When they had parted company, particularly when Sherlock disappeared without prior notice, she had immediately swabbed his mouth. When he refused to disclose about his life in London she had searched for other sources rather than taking whatever distractions he threw at her, including drama from her own life. It rankled, naturally it did, and Sherlock wasn't accustomed to having anyone show dedicated interest in him and who he was - not for a long while now.
He could see that Watson was miserable as a sober companion - anyone who was paying attention could see that, though surprisingly few people in the world actually paid attention to anything. She was intelligent, and it had taken him a few days to realize that she was frightened of her own intelligence and the potential of arrogance and the possibility that she would forget that she did not have control. All of that frightened her, so she had chosen work where she could coast from day to day and not have to face the reality of what she could do. What she could do because people had trusted her to cut them open while they were unconscious and fix whatever had gone wrong within their fragile human bodies.
He could also see that investigation and deductive reasoning had reopened Watson's eyes and allowed that intelligence to shine out like a beacon. She was enthralled by what she could do, the power that she could hold, and it felt safe because it wasn't holding a scalpel in her hands with an exposed beating heart in front of her. And then she had started to trust Sherlock.
It was natural, it happened to any group of people that routinely encountered life threatening situations together. Sherlock had never had any doubts that the work he did was dangerous. He didn't go charging in rooms in a bulletproof vest with a gun at his hip, no, but he had crossed the wrong people more than once in his life and had wound up on the wrong end of knives and guns and hostage situations. Anyone who joined him in his work wasn't exempt, and Watson had quickly been shown just how dangerous seeking killers could be. And she'd come to trust that if she was in danger, if she needed help, that Sherlock would come for her. That was the truth. It wasn't any different than Sherlock's belief that Gregson would come for him if Sherlock was placed in danger because of a case. Sherlock believed in Gregson, but he didn't trust him. That was the difference.
Once Watson trusted him, trusted that he would come for her, then she began to trust other things about him too. That he was a good person. That he had strength of character. That he had a desire to 'recover' from his addiction. None of those other things were true, but trust was like flipping a switch. Trust happened with every piece of a person's mind and once it was there it was difficult to break. People resisted being told what they believed was not true - Sherlock had seen it time and again and marveled each time at the power of the mind to disregard reality. He had gained her 'confidence', so to speak, just as he'd done with any number of people. It was the same set of skills he used on living victims and witnesses, to get them to trust him enough to tell him the details of what happened, but with Watson he hadn't even been trying. Quite the opposite actually. He didn't want Watson to trust him, because once she did the distance that allowed her to be an effective sober companion for him vanished.
Maybe it was different with her other clients, Sherlock suspected that it was, but he couldn't simply tell her about his past, the experiences that made him a person, and have that fix him. He wasn't so much of a narcissist that he insisted his past and experiences were unique or so tragic they couldn't be 'fixed', but he knew the way his mind worked and he knew what had been keeping him sober was the fact that Watson would pop out a drug test whenever he had been left alone or had disappeared to investigate a lead. Watson hadn't tested him in five days now, since they had solved the case with the murderous con man, despite the fact that he'd spent hours alone. Watson trusted him because he had come for her.
Of course he had secret stashes of drugs, both in the house and at other locations; what self-respecting drug addict didn't? Knowing it was there was a comfort, even though at first he had told himself that he had managed for months now and he certainly wasn't dependent on the drug to find a moment of peaceful ignorance. That wasn't the truth. He couldn't stop thinking, seeing, observing, dissecting, and while it was a gift it was also his heaviest curse. He wanted it to stop, just for a few minutes, to make the clarity with which he saw dissipate. Naturally he understood what drugs did to the mind and to the body. He understood that better than most anyone but a medical professional. That ceased to matter when he was kneeling on a counter and prying the compartment from behind a shelf open, the relief so near that just the edge of darkness he'd revealed felt like a wave washing over him.
"Sherlock?" Watson called, her footsteps on the tile in the entryway as the front door closed.
He didn't have time to freeze or contemplate his next action, he simply let his body take over as he closed the panel to the compartment and shut the doors to the cupboard, leaving himself sitting on the counter with the stacks of books he had pulled down. "In here," he called and opened one of the books and held it in his lap. It felt like a farce, almost comical, but he thought he'd done an excellent job of making it appear like nothing was out of sorts.
Watson stepped in, her eyes surveying the room and then settling on Sherlock as she smiled. "Everything alright?"
"Perfect," Sherlock said, though a tug in the back of his mind was reminding him that he'd been so close to what he was seeking.
"Great. I'm making vegetarian lasagna tonight, provided we're not called away on a case," Watson said and walked through the room, a cloth shopping bag in her hand and her hair fluttering over her shoulders and back as she left.
She trusted him and perhaps that was the worst possible thing.