A/N: Spoilers for up to Season 3, Episode 2: The Sign of Three. For the moment, we're disregarding the events of Episode 3, though that may be subject to change.

Prologue: Laying Down the Breadcrumbs

"I warned you not to get involved, Sherlock," Mycroft sighed, twirling his umbrella.

"Yes, well, it's five bloody years too late for that now, isn't it," Sherlock replied snippily. He sank back into his leather chair and stared disinterestedly at the skull on the mantle, pointedly avoiding Mycroft's scrutiny.

Here's yet another sign, Mycroft noted, eyes passing over Sherlock's face before flitting around the room, noting the absence of the rather tasteless red upholstered armchair John favored. Only two years ago and Sherlock would be having this 'conversation' lying prostrate on the couch in nothing but his robe. Further indicators of maturity, though the pouting certainly hasn't changed.

Mycroft fought the urge to sigh then, and rubbed his temples instead – only when dealing with his insufferable little brother did he feel inclined to something so plebian. "Come now, you haven't left the flat in three days, your experiments haven't been touched in longer, and judging from the rather relieved and pleading look Mrs. Hudson bore when showing me in," here he pursed his lips distastefully as he eyed his brother, "you've not eaten in three – no, four – meals."

"Most people would call that an invasion of privacy," Sherlock sulked, repositioning in the chair, as if by edging away from his brother he could avoid this confrontation.

Mycroft did roll his eyes at that. It seemed this was to be yet another rendition of several conversations they'd had before. "We've established we aren't most people, and you don't believe in privacy any more now than you did as a child. Stop deflecting."

Sherlock turned sharply in response to that accusation, gaze narrowing in on Mycroft's face. "Very well. What's my problem, then?" His muscles flexed as he tried to get back under control, tense against the soft fabric of his shirt. "Deduce it for me," he enunciated with a tilt of his chin, annoyed.

Some fire at last, Mycroft relished. He shifted, standing up straighter and clasping his umbrella in front of him, prepared to make his case. "There's an obvious void in your life, previously occupied by one John Watson–"

"Yes, brother dear, I had figured that out for myself, based rather largely on the vacant room upstairs," Sherlock snarked back.

"–hence the use of the word 'obvious,'" Mycroft sneered, little more than a slight upwards snarl of his mouth that managed to convey his rapidly lowering tolerance for Sherlock's childish disseminations.

Sherlock threw his hands up at that, exasperated and motioning for Mycroft to bloody well get on with it.

Mycroft took a deep breath, drawing himself upwards before exhaling softly. "Voids are best fixed by filling them, you know."

His younger brother tossed him a look that contained a small measure of hurt quickly eclipsed with a scoff, responding with, "You suggest finding a replacement John? What a ridiculous notion." Sherlock glanced away with a sniff, "Besides, I already considered it. It would take entirely too long to find someone who hadn't been tainted by the dull mediocrity of the world already. Even John had to be refurbished with my methods, and that took two years. Finding him was happenstance, a 'diamond in the rough,' if you will."

And there's the errant flair for dramatics. Mycroft leaned his weight to the right, placing his hand in his left vest pocket as he adopted a musing look. "I suppose it would be rather irritating to undo a lifetime's worth of vacuous impressions and tedious concerns…but perhaps, it could be groomed into a proper candidate? Someone…not so set in their ways, so to speak?"

His younger brother's eyes lost focus, minute twitches of his facial muscles the only evidence of the myriad of thoughts being considered and rejected in the same breath. Mycroft watched from the corner of his eye as he examined the tip of his umbrella; carefully uncaring was the best way to get through to Sherlock if Mycroft had had the luxury of preparation beforehand. Most days, however, Sherlock neglected to give him much warning prior to causing mayhem, and Mycroft ran close to losing that tenuous hold on his composure. He'd learned this lesson years ago, though – radio silence from Sherlock was not an indication that all was well; he'd allowed his little brother to slip from his attention for a matter of months and it had led to some rather…distasteful habits, not to mention Mummy's tears.

Focus, and lay the challenge…

"–but then again, I had years with you, and look how you turned out," he drawled in a mild, mocking tone, "still just barely above a goldfish."

Sherlock affected some semblance of a smile, "Teaching and patience have never been your strong suit, brother dear. Now get out, you've seen I'm not dead, and I've had quite enough of you. Don't terrorize Mrs. Hudson on your way."

The corner of his mouth lifted, and Mycroft nodded his head. "As you wish; I'll see myself out, then," Beginning to twirl the umbrella, he turned and sauntered down the stairs. Not bad for an afternoon.

"Mrs. Hudson! Tea!" The bellow sailed down from behind him as he passed a blandly pleasant smile to the aforementioned beaming housekeeper, and rang to his ears like victory.

That's the seed planted, then. Let's see what you make of it, brother dear.

A/N: Dipping my toes into the Sherlock!BBC universe. Please let me know if you feel anyone is dramatically out of character, or if the sentences are too stilted - I'd really love some criticism.

Hope to have the next chapter out in a few days (and finally get to some plot).