A/N: Once again, thank you to everyone who took the time to review.

Big gold star goes to toeki, for encyclopaedic knowledge of old Linkin Park songs. Yes, you're right, the title and chapter names all come from track 6 on one of my all time favourite albums Hybrid Theory, entitled "Run Away." I was listening to it when I thought up the idea for this story. It does kinda fit.

SHSHSHSHSH

Guilty By Association: Part III – A Sky of Dust

Sally Donovan had had an excruciatingly long and stressful day.

Lestrade, who was so far in shock one could be forgiven for thinking he'd been stunned with a large halibut, had been more or less useless from the moment he'd ID'd Sherlock's body. He'd barely managed to scrape himself together enough to face finishing Ackenthwaite's case report. She couldn't exactly blame him for that; the DI had not only known the Freak a lot longer than Sally, but at times, actually seemed to like him. To go from co-operating with Sherlock, to arresting him, to investigating his suicide in less than forty-eight hours had been a shock even for Anderson, and their mutual loathing was legendary.

Unfortunately, police bureaucracy being what it was, Sally had had to take up the slack and do Lestrade's work as well as her own. It was almost enough to make her think twice about taking a promotion to DI, if she were ever offered one; and her already healthy respect for her boss definitely went up a notch or two.

As far as her personal feelings went, she wasn't entirely sure she had any yet. Donovan had never pretended to like Sherlock, and she firmly believed him to be guilty of more crimes than the Met would ever be able to prove. Still, she hadn't ever wished him actually dead. And she'd certainly never wanted to see the look in John Watson's eyes when the tough, stoical former soldier came perilously close to bursting into tears during his interview.

In her profession, Sally had met a lot of grieving relatives. It was an unspoken but nonetheless deep-seated assumption that female officers were better at dealing with tears and hysterics than male ones, so she'd often been designated with interviewing weeping siblings, spouses and parents. The suicides tended to be the worst; a toxic combination of guilt and grief and anger and shame all rolled up together as the family tried desperately to make sense of their loss.

John Watson was no exception. It made her wonder just what kind of hold Sherlock had over him, to break a strong man so thoroughly just by stepping off that ledge.

If anyone in the world would genuinely grieve for Sherlock Holmes, regardless of his deceptions, it would be John. Him, at least, Sally could wholeheartedly say she felt sorry for. The doctor had been relatively normal before he got sucked into the vortex of insanity that surrounded his eccentric flatmate; a decorated returning veteran who should have found a cushy GP job and settled down with a nice woman to have a couple of kids. Instead he'd chosen to move in with Sherlock Holmes and spend the better part of eighteen months being his PA, bodyguard, occasional guinea pig, biographer, personal physician, public relations manager, therapist, dogsbody and babysitter all rolled into one. The poor sod was clearly a bit mental; if he had committed any crimes (and she hoped to God he hadn't), she had no doubt they were entirely Sherlock's fault.

Two hours after she should technically have gone home, Sally looked up from her desk to see a tall, dark-haired stranger heading confidently for her bosses' office, umbrella swinging from his fingertips like an old-fashioned gentleman's cane.

"Excuse me, Sir," she called. "Can I help you?"

"I rather doubt it," he replied, pausing to address her in a posh tenor. "Sergeant Donovan, I believe? Detective Inspector Lestrade is expecting me."

Sally tried desperately to keep her hackles from rising at his condescending tone; it wasn't easy, after the day she'd had. "I'm afraid the DI is in a meeting with the Superintendent at the moment, sir," she answered, as professionally as she could manage. "Would you like to wait? I can let him know you're here when he gets back…"

"As a matter of fact, the subject of our meeting also concerns Chief Superintendent Ackenthwaite." He flashed an ID at her that made her eyes widen, and continued, "My name is Mycroft Holmes."

Donovan looked up into the dry, un-bloodshot, perfectly indifferent blue eyes of Holmes the elder and felt an icy prickle ghost down her spine. Comparing that haughty gaze with John's barely restrained misery was like comparing… well, Sherlock with a normal person.

For the first time ever, she found herself feeling something akin to pity for Sherlock Holmes. If this calm, impeccably turned out individual was his closest living relative, mere hours after his suicide, was it really any wonder he turned out to be a psychopath?

Three minutes later, Sally rapped on Ackenthwaite's office door and waited for the muffled shouting from inside to die down before she pushed it open. "Sorry, sir," she said, with a glance from the puce-cheeked Superintendent to a decidedly grey Lestrade. "Mr Holmes is here to see you?" The DI visibly flinched at the name. He scrambled to his feet and went immediately to shake Sherlock's brother by the hand.

"Oh, God… Mycroft… I am so sorry," he said earnestly. "You didn't need to come all the way down here; I've been trying your mobile, but it went straight to voicemail…"

"It's quite all right, Detective Inspector," Mycroft replied, with a small smile made unconvincing only by the tightness of the skin around his eyes and his white-knuckled grip on his umbrella. "I was informed of… events… through my own channels before you were. No need to break the news."

"You're a difficult man to contact, Mr Holmes," Said Ackenthwaite, automatically rising in the presence of such obvious authority.

"My apologies, Chief Superintendent Ackenthwaite," Mycroft replied smoothly, taking the seat Lestrade offered gracefully. "I occasionally employed my brother, and unfortunately, I have had to spend a great deal of time and effort justifying that decision to my own superiors today. It necessitated turning off my phone for the first time since… 2005, I believe."

"Our condolences for your loss, Sir," the Super said perfunctorily. "We'll need to ask you a few questions…"

"Of course; although you should be aware that under the terms of the Official Secrets Act, I am not permitted to divulge any relevant information about any investigations Sherlock undertook for me, involving James Moriarty and his vast and lucrative criminal empire or otherwise. Fortunately, my brother did not count as an official secret except when I was employing him, so I may be candid with you about everything but his work."

Ackenthwaite's brows shot up, as did the level of obsequiousness in his voice when he asked his next question. "What, exactly, do you do, Mr Holmes?"

"I occupy a minor position in the British Government. I am not permitted to be more specific on official records, I'm afraid." Sally fought the urge to bury her face in her hands. The prospect of a Holmes in government was a terrifying one; all the more so because at some unimaginably high level, it probably made him her boss.

"I thought there were rules these days, about politicians employing their relatives," the Superintendent tried cautiously.

"There are. Fortunately, they only apply to MPs, not the civil service. From time to time, I consulted Sherlock on a freelance basis when a problem cropped up that I was too busy, or had no one available, to deal with, much in the same way DI Lestrade here did."

"And the nature of that work? In the vaguest possible terms, of course," Ackenthwaite hastened to add.

"Widely varied, but principally investigative. And all quite above board."

"Of course, sir. You were close to your brother, then, I take it?"

"Not particularly; ours couldn't be described as an especially tight knit family. I was… very invested in his wellbeing, but the sentiment has not been entirely mutual for many years. He tended to find me… a tad overbearing."

"Reckon that might have had something to do with all those impromptu trips to rehab, Mycroft," Lestrade remarked, remembering with a wince.

An odd twist distorted the frighteningly tranquil features for a moment. "Yes; in Sherlock's eyes, my not wanting to watch him poison himself to death was a capital offence," he replied dryly. "But he always was convinced that he knew best."

"You're quite a bit older than Sherlock, is that correct?" The Super asked.

"Seven years, yes."

"So you would have been in a good position to notice any conspicuous intelligence on his part?"

Mycroft arched an eyebrow elegantly. "You mean like the fact that Sherlock had mastered five languages and seven musical instruments by the age of thirteen, and once managed to blow up next door's gazebo using only a ball of string, six ounces of icing sugar and a plastic armadillo?"

Even Lestrade blinked at that one, not having been privy to that particular Sherlockian escapade.

"My brother is… was… a genius." Mycroft intoned, his voice growing distant for a moment. "If you believe nothing else, believe that."

"So the stories in the papers…" The DI began hesitantly. "All the childhood details…" Mycroft's face did the twisting thing again. Embarrassment, possibly, Sally wondered? Or could it be his poor impersonation of a man attempting to repress emotion?

"The anecdotes are, unfortunately, mostly true."

Donovan ventured to chip in, unable to resist. "Even the one about how he got kicked out of university?"

"Yes, Sergeant, even that one, although that was not entirely his fault. Sherlock had been devouring forensics textbooks and journals for years by that point, and even I could see that the forensics lecturer was an idiot to think he could use stratigraphic chromatography to detect bloodstains months after the crime. Sherlock was simply… lacking in subtlety, when he proved it."

"When was the last time you spoke with your brother, Mr Holmes?" The Superintendent enquired.

"On the phone? About… oh, five months ago. In person, it must be more like six or seven. I'd have to check with my assistant to be more specific."

"Seems a long time," Sally observed. "Was that unusual?"

"Not since Doctor Watson arrived on the scene. He did a far better job of looking after Sherlock than I, simply because my brother actually listened to him on occasion; which is more than I can boast. I'm certain you understand, Superintendent, with three… no, four… brothers of your own."

Ackenthwaite shifted uncomfortably in his seat. "How did you know… Oh, of course; a man in your position could get my personnel file."

"True, but quite unnecessary, when presented with the physical data…" He pulled a quick, fake smirk. "But I won't bore you with the details." Sally's eyebrows jumped towards her hairline. If she wasn't very much mistaken, that was the start of one of Sherlock's impossible deductions. Which meant either that the brothers Holmes shared the same freakish talent, or Mycroft really had read that file and was trying to make out he'd deduced it in order to help prove his brother's innocence. At the moment, she couldn't decide which was more likely.

"I did, however, take a few minutes to examine the photographs of the footprints from the school kidnapping," Mycroft continued. "I do not pretend to have spent anywhere near as much time at crime scenes as my late brother; but I must confess to being slightly puzzled as to your reasons for suspecting Doctor Watson's involvement, based on that evidence."

"If you read the forensics report, Mr Holmes, then you know exactly why we are considering Doctor Watson as a suspect," Ackenthwaite said firmly. "And with all due respect, whatever your position, it doesn't give you authority to dictate the course of an active police investigation."

"I would never presume to do such a thing, Superintendent; I'm not my brother," Mycroft assured him smoothly. "I merely observed a few details that were missed by your team; it is my duty as a concerned citizen to point them out to you, is it not? Besides, there was no need to read the report; the photographs were quite sufficient to deduce the height, weight, build and mild infirmity of your kidnapper. The length of stride, smudging of the prints, shoe size, and the fact that he was putting most of his weight onto the heel of the right foot all speak volumes."

Lestrade looked grateful; Sally and Ackenthwaite merely stared open mouthed. How did I never know that there were two of them? Sally wondered.

Mycroft smirked; far more politely than his brother, it had to be said. "Come now; don't tell me it never occurred to you to wonder whom it was that taught Sherlock to observe; it was a game we played as boys. Sherlock simply became rather big headed about it."

"You can say that again," Lestrade remarked wryly. "What was it about the footprints that told you they weren't John's, Mycroft?"

"As I am certain both you and Sergeant Donovan have observed, the good doctor, like approximately eleven percent of the population, is left-handed."

Ackenthwaite rubbed his increasingly colourful nose gingerly, wincing. "So?"

"So, as talented with a handgun as he undoubtedly is after his time in the military, John shoots primarily with his left hand. The kidnapper, however, kept his left arm wrapped around the throat of one of the children while he pointed the gun at her brother with his right. He, therefore, is most likely right handed."

"That doesn't prove anything," Sally snorted. "The Freak was smart enough to tell him to hold it in the wrong hand…"

"Donovan!" Lestrade shouted, appalled.

Mycroft's eyes closed briefly. "Sherlock and I may not have been particularly close, Sergeant," he began, every syllable clipped to razor sharpness. "But I am not prepared to continue assisting the police with your enquiries into his suicide which happened this morning unless you are prepared to speak of my little brother with at least professionalism, since clearly respect is too much to ask."

Sally was mortified. Corrected for insensitivity by a Holmes, of all people. "I… I'm sorry. I didn't mean… I didn't think…"

"Evidently," he cut her off, before turning abruptly to the DI. "How much do you know about Captain Watson of the Fifth Northumberland Fusiliers, Inspector?"

"Um, not a lot," Lestrade replied, slightly startled by the rapid change of subject. "John, uh, doesn't talk much about himself."

"But you are aware that his discharge from Her Majesty's armed forces was on a medical basis, correct?"

"Yeah, he got wounded in Afghanistan, somehow, didn't he?"

"To be more precise, Doctor Watson suffered a gunshot wound that to this day, severely limits the dexterity, muscular strength, and range of motion of his left shoulder; and therefore, his dominant arm. He can't even fully extend it above his head. You may well need to consult a specialist in such injuries, but I personally find it doubtful that he could have marched along a struggling child held around the throat with his damaged left arm without significant pain, if at all. If John were to attempt to do such a thing, it would make far more sense for him to hold the girl with his much stronger right arm, and point the gun at her brother with the left. But as you pointed out, Superintendent, it is not my job to tell you how to investigate; a truth Sherlock never quite managed to grasp."

"And didn't we just know it," Lestrade said, almost wistfully. "Half the time, we all wanted to strangle him; until he came up with something completely brilliant and solved the case in a tenth of the time it would've taken us."

"Sherlock, like the vast majority of highly intelligent people, was a difficult man," Mycroft replied. "His great obsession was his work, to the exclusion of all else; he rarely engaged in any social activity. John had to bully him into eating and sleeping, let alone spending unproductive time with other people. Our… fraternal relationship… was sufficiently strained that he only contacted me when he wanted something, and only then as a last resort. I did my best to assist him, when his requests were not entirely unreasonable. I did promise Mummy, after all."

Very carefully, the three police officers did not react to hearing a man in his forties refer to his maternal parent as 'Mummy'.

Ackenthwaite cleared his throat and redirected the questioning. "What did you speak about when he rang you, Mr Holmes?"

"We exchanged a few phone calls when a private case of his strayed into my remit. I am afraid that the content of those calls, and the case they related to, fall firmly under the 'secret' heading and are therefore out of bounds. There have been a few text messages since, but nothing of any great importance; at least until this morning."

"Yes, that text he set you, something about an apology? What did that refer to?"

Mycroft shifted uncomfortably in his chair. "I made a… misjudgement… recently, which impacted upon my brother and Doctor Watson."

"Please tell me you didn't offer John money again, Mycroft," said Lestrade, rubbing a hand wearily over his face.

"Oh, no; once was quite enough to cement his resistance to the idea, I assure you. No, it was a… professional matter, which I cannot speak more of, I'm afraid."

Sally opened her mouth to ask, but Ackenthwaite beat her to it. "Money? What money?"

"You must understand, Superintendent, that my brother's immediate and obvious attachment to John Watson was quite unprecedented. I was very concerned about the kind of man he was getting involved with, so I tested John's character by offering a financial incentive for information on Sherlock's life; without disclosing our blood relationship, of course. John refused categorically, proving himself to be that rarest of creatures, almost never encountered in my line of work. An honourable man."

"Doctor Watson's a friend of yours, then, is he?"

"More of an acquaintance. I'm afraid I simply fall into the large category of people who found John considerably easier to communicate with than Sherlock. Inevitably, spending time with my brother mostly involved him finding ever more creative ways to irritate me, as is the way of younger siblings."

"So, did you get aquainted with many of your brother's friends? Rich Brook, for example?"

"I know everyone Sherlock could even approach describing as a friend both personally and professionally, Superintendent. And I can categorically confirm that none of them are named Richard Brook. Indeed, I am astonished that none of you have noticed the significance of the name."

"Significance?" Lestrade asked, in confusion. "What significance?"

"Rich Brook is simply an anglofication of Reichenbach, Sherlock's most famous case. Since the individual claiming to be Brook is now deceased, I would suggest you consult the journalist, a Ms Riley, about how he professed to know my brother."

"Please don't take this the wrong way, Sir," Ackenthwaite began, as respectfully as he could manage, "But if those stories in the paper are true, then surely Brook must have known Sherlock in some way; they're not exactly matters of public record."

For the first time, Mycroft looked genuinely sorrowful. "I am not omnipotent, Superintendent," he said quietly. "But I knew my brother better than anyone. And I know that he did not hire an out of work actor to strap a bomb to the best thing that ever happened to him."

"Hear, hear," Lestrade seconded wholeheartedly. Sally tried not to look too obviously sceptical.

"So, you don't believe that Sherlock and John were engaged in any criminal activity, Mr Holmes?" Ackenthwaite asked.

"I believe my brother was, at heart, a good man; and I know for a fact that John is. I thought that eventually, with the Doctor's encouragement, Sherlock would be able to prove his true nature. He has always been… troubled. Volatile, at times. But no matter how much he resented me, I always remained… irrationally fond of him."

The Superintendent leaned forward. "How irrationally?"

"Not enough to blind me to his many faults. But he was doing so well; John was such a positive influence. I hadn't seen him so close to genuinely happy since we were boys."

"Then if he was innocent, why did he jump?" Asked Sally, keeping her tone carefully neutral.

"I was his older brother, not his psychic twin, Sergeant. But, if I had to hazard a guess… You are aware of Sherlock's history with illegal substances. He only managed to give them up, after almost ten years of addiction, for the sake of the work Detective Inspector Lestrade was able to offer him. Following this debacle, even if proved innocent, he knew that he would never be allowed onto another murder scene; reduced to the pursuit of missing cats and unfaithful husbands that provided no stimulation to his considerable intellect."

"Sherlock was self-aware enough to know what would happen next. Without the work, he would have spiralled again, gone back to the drugs. Doing so would have driven John away; he has far too intimate a knowledge of substance abuse to tolerate a resurgence of Sherlock's old habits. My brother's finances would also have suffered enough that he would not be able to afford the rent at Baker Street on his own, so he would lose Mrs Hudson alongside the Doctor. And so Sherlock would have been left alone again, without work, without stimulation, and without the only three people in the world he has ever genuinely liked. It seems that he chose to end his life rather than lose everything he loved."

The silence rang for several seconds. Sally, for one, was in shock at hearing the word 'love' associated with the word 'Sherlock'.

"Now, if there is nothing further?" Mycroft stated briskly, rising from his chair. "I should be getting on; arrangements to make, and so on, you understand."

SHSHSHSHSH

I said this was going to be a three-parter; apparently I lied. I'm thinking one more chapter? Possibly with an epilogue to follow it, haven't decided yet.

P.S If anyone's wondering about the halibut in the first paragraph, it's because I've been watching excessive Monty Python again.