Contrary to popular belief, Sherlock Holmes enjoyed being wrong occasionally. Mistakes tested the boundaries of his knowledge, kept him aware of his limits, and all that. If he didn't make a mistake every once in a while, he wouldn't learn anything unexpected, and he certainly couldn't be quite so confident that the self-correcting mechanism of his reasoning was in top form.
Thus it was not entirely uninteresting to discover that several of the working assumptions about his flatmate he had acquired during the six weeks they had lived and worked together proved to be misleading.
It happened the second time they were arrested. Prior to working with John, Sherlock had never been arrested, not once in all the years he had revisited crime scenes, searched for evidence, and confirmed various hypotheses in an extra-legal fashion. John was slow; John was inexperienced; John was, well, a second person. Always harder to work with a second person, although in this particular case the benefits seems to outweigh the disadvantages. If only they could keep the threat of prosecution at bay.
The first time, the charges had been dropped quietly. It was a trespassing arrest at a not-entirely-empty warehouse, nothing to worry about, really, since the circumstances of the arrest were dubious at best, and the case against them would have fallen apart. At the time, Sherlock credited Lestrade with the gesture of administrative grace. And with more loyalty and influence than he should have, in retrospect.
The second time, too, the charges were dropped. But this time it was Lestrade himself who had arrested them in a fit of pique (the man really need to learn to keep his emotions under control, especially when he acted against his own interests in this way). Their deliverance took the unexpected form of Deputy Commissioner Campbell, who strode into Lestrade's office, locked the office door, snapped the blinds shut, and spoke to Lestrade in a menacing tone that, as far as Sherlock was aware, was completely out of line with the relatively minor house-breaking they had been involved in.
On the way out, she glanced at them for about two seconds with something that could only be described as exasperation. It was curious, to see that kind of expression on the face of the Deputy Commissioner, who was widely known for her precision, efficiency, and impersonal professionalism. (Lestrade had called her "cold" more than once, but he was just as much an incurable romantic as John was, and he obviously imagined a hostility toward his person that was not actually there.) The Deputy Commissioner had once interrupted a conversation Sherlock was having with a local coroner to thank him for his work on a case involving a shooting in Brixton, and he had appreciated her terse style and her avoidance of conversational niceties. If only the entire force were as easy to work with.
"Right," Lestrade said, head poking out of his office. "I think that's all we need from you right now, gentlemen. You're free to go."
Lestrade had a rather hangdog look at the best of times, and contentious contact with his superiors always made it worse. It was a problem a certain type of man had, Sherlock had noticed; he guarded his integrity so carefully that any rebuke to his way of doing things was an affront to his honor. He made a mental note of that, for future reference.
They collected their things and wasted no time in leaving the building. With a look of disgust, John threw his stocking mask into the first rubbish bin they passed. Sherlock suppressed a snort. Clearly the man had a lot to learn about crime detection if he thought his days of house-breaking were over.
They fell into step on the pavement walking toward the main road. It was well past midnight, and the street was quiet except for the sounds of a light rain. Sherlock raised his collar.
"Go on," John said after a moment's silence. His tone was unexpectedly aggressive. Pursed lips, a slight tic in his left eye. Sherlock wondered if the prospect of incarceration had triggered something.
"I wasn't about to say anything," Sherlock said, but John rolled his eyes. Sherlock felt vaguely affronted. As part of a larger campaign to avoid blue streaks even more menacing than his own, he was learning to hold his tongue in John's presence, something that did not come naturally to him. John seemed especially ungrateful today.
They walked in silence for a few moments before John grabbed his shoulder and pulled him into the sheltering entrance to a shop, pushing him up against the plate glass.
"Go on," John said again, now glaring at him. "Tell me about myself. I know you want to."
Sherlock stared back.
"It all makes sense now, doesn't it?" John asked. "You've seen the whole relationship, start to finish. Success on her part, failure on mine."
Sherlock frowned. It bothered him enormously when it was clear that he should know something, and he didn't. He stared at his flatmate, searching. Then John's hand moved almost convulsively to touch his phone, inside his jacket pocket, and the situation began to reveal itself to him.
"You tell me," Sherlock said, fixing John with a level gaze until John looked away.
"Youngest Deputy Commissioner ever," John said in a subdued tone Sherlock sometimes heard from criminals who were relieved, at long last, to admit their crime. "From a family of law enforcement officers, the daughter of a Chief Constable. One of the few woman at that level. Widely thought to be a good choice for the next Commissioner."
John paused, visibly upset, and Sherlock remembered his steady hands on the night he shot the cab driver, as well as his deadly aim.
"Promoted after extraordinary service," Sherlock said, prompting him.
"After the terrorist scare at Victoria Station," John said, finishing the sentence almost absently.
They didn't look much alike, but there was a family resemblance around the eyes. Now that he recognized it, he could hardly believe he'd missed it before.
"She thinks you could have done better than a medical career in the armed forces," Sherlock said.
John nodded. "And that I might have found something more worthwhile, coming home," he said. The words came haltingly. "She might be right. 'Never lives up to potential,' she says. Harry's never had any patience for anyone who didn't know what she wanted."
That sounded eminently reasonable to Sherlock.
"The divorce is killing her," John continued, malice in his voice. "Clara's tired of London and the political side of things and doesn't have time to write, and Harry's just beside herself, especially now she's been promoted. Why has she wasted so much of her life with someone who doesn't share her ambition? Where did she go wrong? Harry never goes wrong."
Intolerant of mistakes, in herself and others; bright; ambitious; loyal; cruel under pressure. John accompanied him for reasons somewhat more complex than those Sherlock had first deduced. Astonishing how an expanded data set changes things. Sherlock thought of the phone and glanced at John's hand, still touching it in his pocket.
John, who was less of an idiot than Sherlock generally supposed, looked at him sharply. "But of course you knew that," John said, suspicion evident on his face.
"Of course," Sherlock said. "Take the laundered shirt, for instance: pristine after midnight, although there were wrinkles in her trousers. She had been home for the day and gone to visit Clara when Lestrade called her and she decided to come back in. The excessive attention to professional dress signals insecurity about her current position or ambition for another, and also an attempt to compensate for whatever reputation she believes she's developed on account of her sexuality or her drinking. But you saw the shirt didn't quite fit; she's put on weight recently, since the separation, and this had to be an older one left at Clara's."
John relaxed, obviously satisfied with Sherlock's answers. He crossed his arms against the cold, cocked his head toward the street, and they began to walk toward the main road again.
"And the surname?" Sherlock asked. He wasn't required to know everything.
"Clara's. At the beginning she didn't want to be associated with Dad, either," John said. "Another story for another night."
Scandal or drinking problems in the family? Sherlock wondered. The latter would explain John's need for structure and his disapproval of any of Sherlock's more practical chemical experiments.
"I didn't know she was still speaking to Clara," John said.
"Not just speaking," Sherlock said. He could almost hear John's curiosity. "No belt."
John contemplated that for a moment. "How many years between us?" he asked.
"Two," Sherlock said. A hopelessly middle-class, orderly family, close enough for competition and comparisons. Correct; the look on John's face confirmed it. Sherlock loved to see his deductive prowess acknowledged, never more so that when it was exhibited under duress, as it was now.
"Is she older or younger?"
"Older." That was easy.
"A childhood friend of both of yours," Sherlock said. There was no other way to explain the unfamiliar nickname on the phone, or John's bitterness over the split and estrangement from his sister, even as she continued to pay his bills.
John laughed incredulously. "I never thought I'd meet anyone smarter than her," he said, smiling with admiration. "That was before I knew you." Something about that smile made Sherlock's chest tighten curiously.
"John--" he said, breaking stride.
They had reached the main road, and John was hailing a cab. Already one set of headlights had slowed down and veered in their direction. "What?" John asked.
"Will she always see to it that charges against us are dropped?"
John frowned. "I don't know. She hates to see me in trouble of any sort."
"Good to know," Sherlock said, filing that away. He ducked inside the cab after John and closed the door.
"221B Baker Street," Sherlock announced, and then, more quietly, to John, "I daresay next time we see her, it will be in a more victorious mode."
"Of course," John said, nodding, without a shadow of doubt, as the taxi pulled out and they headed home.