"Look, I'm sorry, all right?"

There was no response. John pulled the sliding door open a little wider.

"I didn't mean to call you a tit."

There was the slight purse of a lip as Sherlock refrained from a cutting remark on the theme of accidental speech.

John slipped through the gap and into the kitchen. "Sherlock, will you please stop sulking? It's not as if you don't call me five worse things before breakfast."

He watched as Sherlock twisted in his seat to pick another file out of the Scotland Yard box then set it down on the table, which for once was clear of experiments.

"Let me help. I want to help." He moved closer and put his hand on Sherlock's arm, arresting his movement. Sherlock looked down at the restraining hand then up to meet his gaze, eyebrow quirked in an expression of absolute disdain. John wavered but didn't back down. "I want to help," he repeated, a hint of distress starting to creep into his expression.

Sherlock pulled his arm away and picked up another file, throwing it down on the other side of the table. "You can check through the autopsy reports from the first three cases," he said. "Look for any similarities which might indicate the killer's routine and see what you can work out about the weapon used."

He was looking through one of his own files as he spoke and John sank down onto the opposite chair with relief, aware that he had handled the situation very badly. Sherlock clearly knew that he had over-reacted with Constable Hopkins, and if John had kept his cool he might have finally had the leverage to force the discussion he'd been attempting for the past two months. Instead, his angry words had given Sherlock the perfect excuse to get on his high horse and he had taken the hump most decidedly.

To say that Sherlock did not respond well to criticism would be an understatement even by English standards. He didn't always mind 'idiot', if he could translate it as 'foolishly brave', or even just 'incomprehensible', but he had an extremely low tolerance for ridicule. John could get away with a lot under the guise of banter, but you didn't seriously try to take the piss out of Sherlock Holmes unless you wanted to be verbally eviscerated or, in John's case, shut out and ignored, which inevitably reminded him of those early weeks in London and the pointlessness of his solitary life.

John opened the file and started reading though it. From the other side of the table, Sherlock sneaked a glance at his lowered head and became aware of a strange feeling. It felt suspiciously like guilt, which he hadn't truly experienced for many years, and only ever in connection with Mummy.

He squashed the emotion as soon as he recognised it. John was unreasonable on this issue, and attack was the best form of defence. Definitely. He concentrated his attention back onto the photographs he was holding.

For a while it was quiet in 221B, the only sounds being the turning of pages and rustle of folders, together with the scratches of John's pen on his notepad.

"You know, we've never really talked about it."

Sherlock had to force himself not to look up as John's words took him by surprise. Truly, the man was tenacious. It was clear that he found it upsetting when there was discord between them, and yet he seemed willing to risk it for the sake of making his erroneous point.

"And we're not going to now." Sherlock's tone was final.

There was silence for a few minutes.

"He's not the only criminal in London."

Sherlock said nothing.

Deciding that if he was in the dog house anyway he may as well get this off his chest, John tried again. "OK, so he's 'the one that got away', but don't you think you've blown him out of proportion? He's only actually figured in a fraction of the adventures we've had."

"Adventures?" Sherlock scoffed. "What are we, featuring in Boy's Own now?"

"You know what I mean," John insisted. "Fine then: of all the cases we've had, let alone all those you investigated before I came along, how many has he been involved in? And yet you look for him in everything."

He was approaching the critical issue and instinct warned him to back off, as he had done every time so far, but he forced himself on. "Sherlock, the thing in September..."

"Drop it, John."

"I can't!" He'd gone too far to retreat now. "Can't you see that you're obsessed with him? It was bad enough during the actual case, but you've only got worse since then." John hoped his words were registering but Sherlock wouldn't look at him.

"As soon as you decide he's not involved in something, you lose interest and at the slightest hint of a lead you drop everything. What happened in September - that poor family - we both know that wouldn't have happened if you hadn't suddenly dashed off on another wild Moriarty goose chase."

Sherlock's head rose at that. "Nor would it have happened if you hadn't been so desperate for a shag that you went all the way to Yorkshire," he snapped.

John's face paled. "Don't you think I know that?" he demanded. "There's not a day goes by that I don't wish I'd been here."

Sherlock waved his arm dismissively. "It wasn't your fault," he acknowledged. "I don't see why you're still moping over it two months later. You can't save everybody."

"No, but I should be able to save you," John replied. "Even if it's only from yourself."

The unexpected words caused Sherlock's eyebrows to rise in query. He had assumed that John blamed him for what had happened. Certainly everyone else seemed to.

"You got yourself banned, Sherlock," John explained. "These last two months have been a nightmare and then today, when finally they get desperate enough to call you in, you risk it all again and for what? For the same damn reason - bloody Moriarty!"

He sat back, frustration and worry clear on his face.

Sherlock regarded him for a long moment, then dropped his gaze. "John, I..." He paused, then started again. "I admit that I had not entirely grasped the nature of your concern," he said, fingers absently straightening the photographs in front of him. "But while your... consideration for me is appreciated, I must make plain to you that I would still class catching Moriarty as my number one priority."

John bit back a smile, suddenly reminded of that first conversation at Angelo's all those months ago - Sherlock always got more pompous when he was feeling disconcerted.

"Fair enough," he said, feeling infinitely better to have said his piece at last. "But I'll be here to make sure that everything else doesn't fall by the wayside."

"Fine," Sherlock agreed, shuffling papers again. "Good." He glanced up and produced a small, almost shy, smile.

"Tea?" offered John.

"Lovely."

oOo

Half an hour later, Sherlock observed that John's attention was no longer focused exclusively on the reports in front of him, but was now being interrupted by frequent glances in the direction of the fridge. A rumbling sound bore out the obvious conclusion and he determined that a distraction was needed if the day were not to deteriorate into an abyss of culinary excess.

He glanced at his watch. "Three o'clock," he announced. "Perfect." He jotted down an address and passed the note across the table. "I need you to go to Moira Pickering's office and talk to her colleagues," he instructed. "Find out her routine, where she went for lunch, how she travelled to work, who she regularly came into contact with, that kind of thing. If you leave now, you should have time before they close for the day."

John took the address with some reluctance. "I'll just grab a quick sandwich before I go," he said.

"No time for that!" Sherlock declared, making 'get up' motions with his hands. "Half of the food Billy dropped off last night is in still the fridge. You can eat later."

John looked unconvinced.

"Angelo's finest," Sherlock added, temptingly. "Something to look forward to when you get back."

A rather sly expression crossed John's face. "Fine," he replied. "I'll wait until later - if you share it with me."

Sherlock opened his mouth to protest, then closed it again. It wouldn't kill him to let John have this victory. "I'll eat a bit," he promised.

John was reading the address, which was fortunately not far away, as he trotted down the stairs and he didn't see Peter standing at the bottom until he almost ran into him. He lurched to a halt on the last step, finding himself disconcertingly nose to nose with the dour man.

"Oh," he said, attempting to convert his startled cry into some kind of greeting. "Hello Peter, can I get by?"

"Shopping," replied Peter, who seemed to personify the 'man of few words' philosophy.

"Shopping," echoed John, not feeling hugely enlightened by the conversation thus far. He edged to the right, hoping to squeeze past, but Peter didn't move. Realisation dawned. "Oh, right - the shopping. Yes. Thank you. Erm... look, can I pick it up later? I'm just on my way out now." He waved his arm in the direction of the door. "If I could just..."

"Peter, dear, do stop looming," Mrs Hudson's voice came from the front door and Peter half turned as she approached.

"Now, I was just round at Mrs Turner's and I've had a wonderful idea," continued Mrs Hudson. She did, indeed, look unusually perky as she regarded her nephew. "You can do up the basement flat!" she told him with the air of one proffering a great treat. "It will do you good to make yourself useful and you could even move in there for a while until you get sorted." She looked delighted at this prospect. "I'm sure it won't be a big job. Tim said he'd give you a hand and there's some furniture in storage which should be just the ticket..." her voice trailed off as she headed towards 221A, turning back at the door.

"Do come along, dear," she prompted. "No time like the present."

It briefly seemed as if the prospect of actual work might be enough to lift Peter from his apathy, and John offered him an encouraging smile, but the moment passed and he trudged off after his aunt, at last allowing John to escape the staircase. Mrs Hudson's flow of suggestions were still audible as he grabbed his coat from the alcove, and he smiled to himself. Sherlock might be hard to live with at times, but John didn't think he'd swap him.

oOo

It was nearly six o'clock when John finally got home, which was a bloody long time since breakfast. Only the incentive of getting Sherlock to eat something had kept his feet in motion as he passed the chip shop. They wouldn't normally be his first choice for dinner, but there was something about the smell as you walked past that seemed to tap into an inherently English instinct. The tang of vinegar, the briny evocation of seaside holidays – fish and chips was on the 'most missed' list of many an English soldier.

Sherlock had better keep his word about dinner, John thought grumpily as he stomped up the stairs. He walked into the living room, but it was empty. Well… it was covered in crap, as usual, but decidedly devoid of Sherlock.

"In here, John," came from the kitchen and he walked through to find Sherlock exactly where he had left him, although there must have been motion at some point as he now had John's laptop open on the table.

"Where's yours?" John enquired, not even bothering to inject any indignation into his voice.

Sherlock waved his arm in a gesture which could either mean 'Somewhere in that direction', or simply 'Your question is irrelevant'.

"Moira Pickering was surprisingly coy about her personal life when posting on her own Wall," he stated. "But hopefully she's been less discreet on other people's." He hit the Enter key, then turned his head. "Anything interesting?"

John walked round to peer over his shoulder. "Facebook?" he queried. "What are you doing on Facebook?" He looked again, an image of Moira smiling back at him. "How did you..."

Sherlock snorted. "Lestrade wouldn't let me take her laptop," he said disgustedly. "But it was already signed in to her Facebook account so I sent myself a friend request before I handed it back, and now I've sent my own to the people she chats to the most."

John stepped closer and reached in front of him to click on the Profile link. "Kelli Jones?" he queried. "Who the hell is Kelli Jones?"

"I set her up six months ago," Sherlock told him. "She's been invaluable for finding out about people's lives." He looked round, noting the 'I'm no wiser' expression. "Well I can hardly pretend to be obsessed with clothes and boyfriends under my own name, can I?" he challenged, brushing a speck of dust from the sleeve of his immaculately tailored jacket. "What?" he demanded, as John's lips twitched.

"Nothing," John replied, controlling his thoughts before another argument erupted. He looked at the screen again, and his eyes widened. "Is that..." He blinked a few times. "No, it can't be." He leaned forward, peering closely at the photo which had caught his eye and almost squashing Sherlock against the edge of the table. "It is!" he said. "It bloody is. That's Janet."

He stepped back, pointing angrily at the pictorial representation of the fictional Kelli Jones. "Explain to me why your alter-ego looks exactly like my girlfriend from Uni."

"I blurred it a bit," Sherlock protested. "I needed an image and it was right there on your computer. Anyway, it's ages old, no one will recognise her."

"It's not that old," objected John, indignantly.

Sherlock huffed. "It took me six minutes to find a snap which didn't look hideously dated," he complained. "Really John, your taste in women is only slightly less questionable than your taste in clothes. And as for the hair..."

"Well, what makes you think anyone is going to accept friend requests from some woman they don't know?" John interrupted. "Especially one with a dodgy haircut," he added sulkily.

"You'd be surprised," Sherlock answered, indicating the left hand side of the screen. "Look - 347 alleged friends, not one of whom has the slightest idea who I am. Some of them accept any request just so that they appear more popular; then once you have one member of a social circle, you're a 'friend of a friend' and that's enough for most of the rest. It's madness." He shrugged. "But it's useful madness."

John shook his head. "Janet married the Captain of the First Fifteen," he warned. "That's the rugby team, in case you've deleted sports terminology. And Doug is built like a tank - if he finds out about this, you'd better run for cover. And don't expect me to shoot him for you, either," he added. "Because a month in traction might teach you a lesson."

He looked at Sherlock, who was clearly paying him no attention whatsoever, and sighed. Who was he kidding? He wouldn't let anyone hurt the arrogant sod, no matter how much he deserved it. John settled for ruffling his hair, which produced the usual huff and hand flapping, then headed for the fridge.

"Ready to eat?" he enquired. "I'm starved."

"What?" Sherlock asked absently, one hand smoothing down his curls. The rattle of the fridge door snagged his attention and he looked round, then jumped to his feet and stepped across the room, reaching around John to push the door closed again.

"Notes first," he declared.

John's shoulders sagged and he leaned forward until his forehead was resting against the appliance. "But I'm hungry," he moaned plaintively.

"And you call me melodramatic!" snorted Sherlock. He put his hands on John's shoulders and steered him away from the fridge and out of the kitchen, pushing him along until he was standing in front of the fireplace.

"Right, I want to sort out some notes on the four cases," he said. "You can stick them on the wall for me."

"This is why I worked my arse off in medical school," John replied grumpily. "Sticking notes on a wall. Good job I paid attention in class."

Sherlock moved to John's left and regarded him carefully. "You're all right for a bit," he decided. "One hour, and then dinner."

John looked back at him, drawing energy from the excess which seemed to emanate from Sherlock in his 'case-on' excitement. "Fine," he agreed, at last. "But you're eating too." He hung on to the one victory he had managed today.

"Yes, Doctor." Sherlock held out a pad of large post-it notes and a pen, which John took from him resignedly.

"Right," Sherlock started. "Case one: Richard Simpson. His body was discovered on Wednesday the 27th of October; death was estimated to have occurred on the preceding Sunday." He glanced at John. "Don't write this one down, I already did a note." He handed it over.

"Is this in code?" asked John. Sherlock looked affronted. "Never mind," said John. "I'll write them all myself in the interests of consistency." And in case anyone ever wants to actually read them, he added mentally.

Sherlock regarded him suspiciously, then carried on. "Twenty-eight years old, white, gay, single, Londoner born and bred, lived alone in what was the family home in Putney. Brought up Church of England, but stopped attending services when his parents died in a car crash two years ago. He worked as an office manager at a marketing firm."

He looked at John's busy scribbling. "Got that?" he asked.

John's tongue was poking out of the corner of his mouth as he concentrated. "Got it," he said at last, writing 'Case One' at the top of the note and sticking it on the wall.

"Second murder," Sherlock carried on. "Philippa Saunders: body discovered on Tuesday the second of November, again estimated to have died the Sunday before. Thirty-five years old, black, also from London. She made a good salary as a legal secretary at some firm with an unfeasibly long name."

John chuckled. "That's a bit imprecise for you, isn't it?" he asked.

"Unless it's likely to be relevant, I'm not going to clutter up my hard drive with a list of 'London's most overpaid'," Sherlock told him. "Anyway, at the speed you're writing, you'd starve to death before you got to the end. I'm only thinking of you."

Ignoring the resultant snort, he carried on. "Divorced five years ago, no children. She lived in a studio apartment in West Hampstead. No identified religious affiliations and the police haven't yet tracked down the ex-husband."

He waited for John to catch up. "Third case a week later: Neil Benson. Thirty-two years old, white," he caught John's eye, "not yellow - it was indeed a bad photo - originally from Dorset, moved to London in his twenties. No living family, he spent two months in rehab after losing his wife to cancer, seems to have been clean since he got out a year ago."

"Poor sod."

"They were all murdered, John."

"All right, poor sods."

Sherlock felt he was missing something, but he pressed on. "Regularly attended 'Alcoholics Anonymous' meetings; there's a statement from his sponsor."

"Not massively anonymous then," John observed.

"She found the body."

"She?" queried John. "That's unusual - sponsors are usually the same gender."

Sherlock brushed this aside. "He held a fairly menial position in a call centre, which she helped him to get - the boss called her when he didn't turn up for work on Monday the eighth of November. She found him that evening at his ground floor flat in Acton, death was estimated at early Sunday the seventh."

"Religion?" queried John, who strived for consistency in his notes.

Sherlock sniffed. "Some sort of indeterminate Christianity, from what I can gather. Right," he continued. "You can do the last one later - tell me what you found out from her office."

John finished sticking the third sheet to the wall and pulled his own notebook from his pocket. "OK, well I spoke to her boss," he checked his notes, "Robert Thompson," he read out. "Not particularly helpful. One of those large, blustery men. Very officious. Said he'd already spoken to the police and that Moira was a quiet girl, no trouble, he had nothing more to add."

"When you say large..."

John bristled. "No, I do not just mean in comparison to me! Will you give it a rest? It was one time and that thug would have looked large to you too if you'd been tied to a chair and concussed when you saw him."

"He was five foot eight."

John gritted his jaw. "Well Mr Thompson was at least six feet," he said. "Possibly even six foot one, which would make him taller than some people who give an illusion of great height which is mostly hair and flouncing."

He turned back to his notepad, leaving Sherlock mouthing 'flouncing?' unnoticed.

"He was solidly built too, but probably not as old as he acted. The pompous type. Anyway, the girls in the office were much nicer." He smiled.

Sherlock rolled his eyes. "When?" he asked.

John looked at him blankly.

"You've obviously asked one of them out, so when is it? At what point of the week am I suddenly to be abandoned?"

"It's not a date," John defended. "I asked about Moira's love life and they said they didn't know, but they were giving each other looks, so there's obviously something there. I thought if I got one of them on her own she might say more."

"How self-sacrificing," commented Sherlock. "If Facebook comes through, you might be saved this meeting with..."

"Vanessa."

"On..."

"Wednesday night," John admitted, grudgingly. "And no, you can't come too. I'm sure I can manage to extract one bit of information all by myself."

"One would hope."

A tap on the open door curtailed the conversation, which was probably just as well. "I've brought your shopping up, boys," called Mrs Hudson. "I'll just pop it in the kitchen, shall I?"

She glanced at the notes as she walked in. "Oh, have you got another case, dear? How lovely." She patted Sherlock's shoulder as she passed and he flashed her his unholy grin. John wondered if everyone who came into regular contact with him developed this skewed perspective towards serious crime, or whether you actually had to live with him for the fear of 'bored Sherlock' to over-ride everything else.

"You might want to put some of these photos away if Peter comes up," she called from the kitchen. "He doesn't like the sight of blood, you know."

John threw a horrified glance at Sherlock and dashed through the doorway, gathering up the autopsy images hurriedly. "I'm so sorry, Mrs Hudson," he apologised. "We should never have left these out."

She smiled at him. "Oh, don't mind me, dear," she said. "I've a much stronger stomach."

She was looking at the laptop now. "Why do people write their names in such a funny way these days?" she asked. "I would never spell Kelly like that."

"Apparently 'i' is the new 'y', Mrs Hudson," Sherlock called through from the living room. "I have it on good authority."

"Good authority?" echoed John. "Hang on… Did you say you'd set this up six months ago?" He was thinking back. "Was that when we were looking into that theft at the sixth form college?"

Sherlock glanced round. "One should never disregard expert advice, John," he said. "There was nothing about Facebook those girls didn't know."

"I suppose the fact they all swooned over your 'Byronic good looks' didn't hurt."

Sherlock managed to look both dismissive and smug at the same time, which John couldn't really begrudge him. Considering that he was used to working in an atmosphere of almost unmitigated hostility, a bit of adulation had made a nice change once he'd got over the fear factor.

"Adrian next door was always trying to get me to join Facebook," Mrs Hudson said as she moved back into the living room. "But I told him I didn't want to poke people."

She sighed. "He always seemed such a nice young man," she said, regretfully. "Who would have believed that he was carrying on with that artist chap all the while? And to think, Sherlock, if you hadn't noticed that paint on his trousers no one might ever have known."

"It wasn't on his trousers, it was inside his collar."

Mrs Hudson allowed this correction to wash over her.

"Of course it's left Tim very lonely, poor boy." She eyed Sherlock appraisingly, to which he seemed completely oblivious. John hid a smile - Mrs Hudson was an incorrigible romantic and still held out the hope of one day having 'married ones' of her own.

He watched as Sherlock added some more notes and then rearranged them to his satisfaction, long fingers a blur as he worked, happily unaware of the plotting landlady behind him. He was almost hypnotic like this, concentration on his face, in his own world. John could watch him for hours.

After a while, John shook himself and forced his attention away, only to find that Mrs Hudson's gaze had moved to him and her eyes were most definitely twinkling. John coughed, then gave her the blandest smile he could manage and turned to tradition.

"Tea?"