What follows is pretty much all plot-business rather than LURV and sentiment. I happen to think it's fun and interesting, but it's also just the vital gears of narrative falling into place and letting the drive-chain of the story do its work.

John was John. As one obstacle after another fell before Sherlock, and they penetrated deeper and deeper into the confines of Buckingham Palace, he looked on in stunned and shocked amazement, unable to guess the nature of the magic trick that cleared all paths for them.

It was simple, really—obvious, if John had only thought about it. All one had to know was what Mycroft was, and that Beemish's little mob of security people had been present in the hospital waiting room when Sherlock announced his destination. At that point only two things could have happened.

John and Sherlock might have ended up sitting in a windowless room, restricted for the foreseeable future. After all, it was perfectly plausible that Her Majesty's Secret Service didn't want Mycroft Holmes' unpredictable maverick little brother mollocking about in the nation's most sensitive affairs. Or…

Or this. For some reason they were willing to suffer his intrusion—were perhaps even desperate for him to intrude. Taking into account their frenzy over Mycroft's current condition, it had seemed a worthwhile bet that they would be willing to bring him in. Every guard who stepped aside to let them pass, or who directed them down yet another quiet corridor, confirmed he'd won his bet. That did not, however, explain the nature of their desperation—it only illustrated its depth and intensity.

Sherlock knew how serious things were when they passed from polished perfection to corridors carpeted with slightly worn runners and flanked with wainscoting that showed the passage of years. They were no longer dealing with the façade of government, the crisp, clean show put on to impress outsiders. They were now in the cloistered rooms where elected officials and political appointees seldom came, but where unsung career civil servants ran the empire over the course of decades…decades? No. Centuries.

A dusty little man in a formal morning coat met them at an intersection of corridors flanked with well-kept but far from new chairs. He tipped the two men the merest hint of a bow. "This way, please."

Moments later they entered a room with ancient leaded glass windows on either side paned in wavy glass that looked out over a small garden at the left and a vast expanse of lawn on the right. He'd been in this room before—seldom, though, and never happily. The last time had been immediately after his "death." The time previous he'd been with Mycroft and Irene Adler.

An old man sat behind the broad oak table placed under of the windows looking out on the garden. Sherlock found himself automatically licking his lips. "Uncle William."

"Sherlock." William, that old lizard, showed no sign of dismay…though he had to be deeply dismayed to be meeting Sherlock here, and now. "I'd say 'how nice to see you,' but you'd only point out the nature of the lie, so I shan't bother. Do sit down, please—and you, too, Dr. Watson. I've ordered tea and sandwiches. You can have a decent meal while Sherlock and I have a little discussion."

John frowned—an expression that reminded Sherlock of a worried fox hound picking up a strange new scent. "Um, thank you. And…you are…? Who?" For all the gentle phrasing and the manner of a slightly absent-minded professor, John's voice and eyes made it clear he was demanding an answer.

Uncle William merely smiled, eyes half-lidded, a wrinkled enigma.

"He's William Emery, Esquire, Mycroft's and my great-uncle. He is to Mycroft as Mycroft is to a corner greengrocer. If Mycroft is Her Majesty's Fixer, Uncle William is the fixer's fixer."

"You do so like ripping the dustsheets off of that which is decently shrouded in obscurity, Sherlock. No sense of discretion at all," William complained. He turned his attention back to John. "He is, however, correct enough, insofar as it goes. I'm largely out of action these days—Mycroft has come along nicely, and more and more I can leave everything in his capable hands. Every so often, though, they do call me out of my peaceful retirement to…shall we say I am asked to unravel the occasional nasty, tangled skein of yarn?"

John looked little the wiser…but he also had the resigned look he often seemed to get when dealing with the Holmes brothers and their associates. "Yeah, okay, good enough." He sat in an elegant light wooden Chippendale armchair with thin leather upholstery. He looked at his two companions with a flash of humor, and gave a mock-gracious flick of his hand. "Keep calm and carry on, then. God forbid any skeins be left tangled."

William glanced at a second armchair. "Sherlock? If you'll be seated?"

"I'd rather stand, thank you."

"You were always the most defiant boy. I had hoped you'd grow out of it—such a waste of potential tossed away on worthless displays of resistance—but I see age has not withered nor custom staled your infinite contrariety."

"Not content with having taken possession of one Holmes brother? Poor Mycroft—does he know you don't just want an heir, but an heir and a spare?"

"He's the one who continues to hold out hope for you, Sherlock. As far as I'm concerned you're barely worthy of consideration, and then useful only in melodramatic efforts such as you recently endeavored for us: splashy and dramatic, but not requiring much subtlety. Finding and eliminating Moriarty's brute squad was useful—but hardly elegant."

"And elegance is always a major consideration in bespoke wet-work."

"If only your compassion matched your wit. A pity, really…you could be great, if you didn't think people too much bother compared to your precious puzzles. Mycroft is worth a dozen of you."

Sherlock's temper, never entirely placid, ignited, and the words shot out—a fast rat-tat-tat of observations, queries, and conclusions. "Mycroft, unfortunately, is not here to serve you—which is why, of course, I am. Otherwise you'd be appealing to him to help you deal with your ongoing project in the Middle East. How do I know the project is in the Middle East? Because Mycroft finally decided to call me home—and then went silent on me. Therefore I conclude that he had a mission, that the mission was one I might have disrupted had I remained in Islamabad, and might have damaged even here, had I known enough. Likewise, a project for which I have some background that would permit me to be useful to you know. So, what is Mycroft's little secret? More wet-work? No—too prosaic. Mere assassination can be entrusted to lesser administrators. No—something more challenging, or Mycroft wouldn't be your vital player. A project of his own, then, and subtle—and now in some way threatened. An event to be planned for? No…no." His eyes locked into focus, then, like a hunting cat who has just committed to an attack. If he'd been a cat his hips would have been shimmying and the tip of his tail fluttering like the feline version of jazz-hands. "Not something threatened. Someone threatened. An agent. Someone embedded. Someone in a position to not only supply information, but to sway decisions. Someone in deep cover in very high places—or very low. Someone who's not safe, anymore." He looked at William with a burning hunger. "Am I right? I am right! Who is it, Uncle William? Who?"

William's eyes narrowed, and he studied Sherlock with distaste. "So much brilliance, but no discipline, and absolutely no common sense. Think, you stupid little boy—think! A player that well placed, and that vulnerable? Who would know who it would be? Who can contact him—or her? How many were allowed to know the secret, Sherlock?" There was a tap at the door, then. William sighed. "Think about it, you young hound. Think about it while your friend and I have tea. " He raised his reedy voice, shouting, "Come in, Albert. You're not interrupting anything."

Sherlock threw himself into the armchair in front of the room's small fireplace, where a wood fire burned to push back the chill of autumn. "This is a waste of time."

"Tea, my dear Sherlock, is never a waste of time. Civilization is humanity's one great accomplishment, and tea is the pinnacle of civilization."

The tea service was comfortingly fussy and Victorian, covered in hand-painted pink cabbage roses. The tea was strong black India tea. The sandwiches, arranged on a three-tiered serving platter, were plentiful and varied. William encouraged John to eat his fill. John obeyed. He and the older man quickly found topics in common to discuss: a mutual fondness for smoked salmon sandwich fingers and egg-salad toasts; a conviction that strong black tea with milk and sugar was a primary food group in its own right; and the shared observation that active duty was character-forming—but that the character formed was not always optimal.

Through it Sherlock brooded, as openly and intrusively as possible. He detested finding himself at odds with his great-uncle. There were few people who could disassemble Sherlock's ego at all, and none who could do it with quite the same level of zestful efficiency. Mycroft could come close, but Mycroft was…kind-hearted. William had all of Mycroft's finesse and discipline, but shared with Sherlock a certain delight in savagery. Mycroft would do only such harm as he felt was both earned and necessary. William would do as much harm as he thought would leave his victims useful—but bleeding and begging for pain medication.

When the tea trolley had at last been rolled away, William took a few extra seconds to ensure he was neat and crumb free, then lifted his chin and addressed Sherlock, who was still pouting by the fire. "And have you managed to refine your theories, Sherlock?"

"An embedded agent in a powerful but vulnerable position in the Middle East, whose actual identity is known only to Mycroft and a very small set of others: I would suspect no more than one or two others. You've just gotten word that the agent has been identified and is being targeted by enemies—but you don't know who the agent is yourself, nor do you know who else Mycroft entrusted with the knowledge. Even if you did know who Mycroft was working with, you couldn't trust them—someone, after all, leaked to your enemies. If you get this wrong you lose a well-placed agent…and possibly the upcoming project, as well."

"Yes. Very good. And?"

"And you think I can determine who the agent is, and how to warn him or her safely, without alerting Mycroft's middle-men."

"You don't think we want you to capture the leak and cancel the project?"

"He's got 'teacher voice,'" John said in mild amusement. "That's a trick question. Now I know who drills the Holmes boys."

Sherlock shot John a furious glare, then snapped his attention back to William. "No. You want the plan to proceed, and you want Mycroft's agent warned. But you also want to watch the behavior of the leaker. Depending on what you see, your decision may be assassination, feeding the mole misinformation, or something as simple as an apparently ordinary reassignment, taking the two-timer out of play but still under your eye. "

"Nicely reasoned."

"I'll need access to all Mycroft's records."

"Not possible."

"Make it possible."

"I can't. Even if I wanted to, there's no way you would be allowed access so much of Mycroft's information. You're not that trustworthy."

"Yet you're trusting me with this."

"Yes. With great reservations. You are brilliant, Sherlock. You always have been. But you are selfish, immature, impulsive, capable of vengeful cruelty, and highly erratic. Not to mention being terrifyingly ignorant of much of the world, and utterly unaware of the ways that ignorance can affect you and others. I have read in Dr. Watson's blog you did not know the world rotates around the sun—and that you thought it made no difference to you whether it did or did not: that you would solve your cases just the same. But it would make a difference. Earth and its life could not survive in a Ptolemaic system. You would have no cases…you would not live in the first place."

Sherlock's jaw clenched, and he fought his temper down like a hot-headed schoolboy facing a hated schoolmaster. "And your point, sir?"

"You do not know or even imagine the consequences of your own ignorance…and you refuse to take responsibility for the consequences when you act out of that ignorance. You've already done inestimable damage to critical projects out of combined ignorance and vanity. I do not intend to allow you to do that again."

"Very well. Allow me to educate myself: give me access to Mycroft's information."

"No. Tell me what to look for, and I and those assigned to Mycroft will search and tell you what you need to know."

"Unacceptable."

"You have your own resources, Sherlock. I suggest you use them. What do you need me to look for from Mycroft's files?"

Sherlock glared at William. "I could refuse to do this."

William's bushy white brows flew up in skeptical surprise. "Could you? Really?"

Mycroft hovered between them like the ghost of someone already dead.

Sherlock stood, then, and paced a turn around the little room. His eye traced the shoulder of an elegant Ulster coat hanging from a coat hook by the door. He stroked the curved handle of the umbrella tucked into a blue-and-white Chinese floral umbrella stand. "No. Not really." He turned back to look at William. "I need a precise of what you can give me surrounding the issue. Someone's got to know something—you can't send me in blind. There are too many things to rule out, and too little time. Can you do that much? Even if the agent's name is secret, the broader details of the project can't be." He gave a bitter smile. "After all, Mycroft's not me. He's the responsible one. He'll have kept his people in the loop."

William nodded. "I can do that, yes. Anything else?"

"Where is Mycroft's ring?"

William sat up, then. "What?"

"His ring. Where's his ring?"

"It's not with him?"

"No. I checked his possessions at the hospital, and reviewed the inventory. Unless someone's successfully hiding something from me, he didn't have it with him when he went in."

"Impossible!" William looked as shocked as Sherlock felt.

John frowned at them. "He was going to be in hospital. Most people leave off their jewelry if they know they're going in hospital."

William and Sherlock both rounded on the doctor, scowling. "Not the ring," William said, and Sherlock added, "He might have slipped it on a chain to wear around his neck or as a bracelet…but he wouldn't have left it."

"What's so special about the ring?" John asked, bewildered now.

"That is Mycroft's business," the older man said, sharply, closing off conjecture. He turned back to Sherlock. "You think he left it behind to mark something in some way?"

"You and I and a very few others are the only ones who would see the absence of the ring as a clue. Mycroft would have counted on us—on me noticing, but only if something went so wrong that I had to be called in. It was the perfect message: one that would never be delivered until it had to be delivered. I would only know if Mycroft were dead or dying."

"Yes. In which case finding the ring may well provide a second message."

"Yes."

William nodded, almost to himself. "Yes. Very well, Sherlock. You do what you do best—and I'll start work here. You've given me some ideas and some things to look out for." Even as he spoke it was clear he was going into his own private mental space, planning and considering.

Sherlock caught John's eye, and gave a slight head-jerk toward the door. As John rose, he said, "Be sure to get back to me. Goodbye, Uncle William."

"Yes, yes…" He barely noticed his guests leaving—nor did he notice when Sherlock slipped the umbrella out of the stand and hooked it over his arm.

While walking down the corridors, tracing the invisible clue of their reverse passage, John asked, "Where was that? Besides Buckingham-bloody-Palace?"

"Mycroft's rooms."

John stopped cold. "You mean Mycroft lives at Buckingham Palace?"

"You know he does—you've been before! Do you pay attention to nothing, John?"

"I thought he'd been called in. Emergency. You know—that kind of thing."

"He's a member of the Royal Household. Further the deponent sayeth not. He is what one might call 'admirably placed to see to matters requiring both great latitude of authority and even greater discretion.'"

"He lives here. In bloody Buckingham-bloody-Palace."

"Yes, John. It's convenient for him…and for his masters."

John shook his head in stunned disbelief. "Here. Buckingham Palace. And you living in Mrs. Hudson's first storey flat?"

Imitating Mrs. Hudson's inflections,Sherlock said, wryly, "It's a funny old world, then, isn' it?"

He might have laughed, then, but he didn't. The weight of Mycroft's umbrella seemed to weigh him down beyond all hope of laughter.

Author's Notes:

William Emery, Esquire: if it helps you imagine him, my brain decided in the midst of writing him that he looks and seems very nearly exactly like Sir Ian McKellan as Magneto in the X-Men movies. My mind apparently thinks it takes someone of Sir Ian's caliber to hand Sherlock his arse on a platter.

I am considering whether or not to post "Adler Alerts" on episodes. While it would make some readers feel safer, it would steal the pleasing element of surprise from readers who don't mind Irene. I will continue pondering. If you've got something that is A: brief, and B: has a legitimate claim to being noted in my pondering, you may send me a polite IM.