Seventeen hours. That's how long it takes Mycroft — despite utilizing many of his best connections and every ounce of his charm — to get his brother checked out of the hospital and ensconced (relatively) safely in the ruins of 221B Baker Street. And even then, Mycroft has had to sign a sworn affidavit that someone will be with Sherlock for the next twelve hours, which is not true, probably. In all likelihood, even if a guard or watcher was assigned, Sherlock would disable and escape them, and they would be lucky to live through it. Technically, though, Mycroft is thinking about the ways that Sherlock would not be alone: CCTV, the various undercover officers assigned to him, and the incontrovertible fact that if Sherlock left the flat, it would be to find Dr. Watson, in which case he would be "alone" for only the brief period of time required for travel.
Sherlock hasn't spoken since asking about Dr. Watson, not even when a clumsy technician jarred his left hand, which was looking less and less like the delicate appendage it had been and more and more like a grotesque sort of mutated plum. They settle into the car at last, and the driver smoothly accelerates, thankfully not jerking Sherlock's spinal cord.
They do not speak, make eye contact, or touch for the first few minutes of the drive. Sherlock stares out the dark-tinted window as if waiting to see Dr. Watson standing on a street corner, as if staring hard enough will make it happen. Mycroft is carefully not noticing the mechanical way Sherlock opens and closes his good hand, as if limbering up for a fight. Mycroft is also, after a few minutes, pointedly ignoring the glare that Sherlock has turned his way.
Sherlock really is dreadfully predictable, with his dramatics and histrionics and general indulgence in emotional excess. Once upon a time, Mycroft might have counseled him to leave the emotional aspect alone, but after withdrawal, just seeing Sherlock act human was enough. Instead, Mycroft telegraphs his disapproval in other ways, the current method being talking aloud about Mummy's plans for the yearly Holmes Winter Gala. This year, to match the theme to her chosen charity of choice, she is planning to recreate a medieval court complete with jousting, bards, and (her favorite part) a faux-Green Knight to ride in and challenge their father to a game of chess.
Sherlock somehow manages to ignore this monologue, choosing instead to incrementally intensify the body language cues that reveal his rage, his fear, his sorrow. That Mycroft is simultaneously having Anthea work her magic on a Blackberry will not escape notice, but the underlying message — do not allow your emotions to override your work — will come through clearly and be summarily ignored, as usual.
After depositing Sherlock at 221B Baker Street and instructing the delightfully batty landlady to hover, Mycroft turns to Anthea. "Report."
"Still looking, but we've narrowed it a bit." She sends him a map image, with concentric circles marked with probabilities. "Almost certainly in the docks area, given—"
"Yes, yes, I know. Any luck with Sherlock's homeless network?"
"They've not seen anything yet, but they're watching. They send their regards, as well, sir."
"Mmm."
"Oh, and DI Lestrade would like to see you in his office."
"Very well." Mycroft reaches into his pocket and extracts from it a badly battered bag of Maltesers, pops four in his mouth, and stares down Anthea as if daring her to say a word. Of course, because it's Anthea, she doesn't say a thing, and because it's Anthea, he purses his lips, closes the bag, and places it across the seat from himself, telegraphing his (utterly false) disinterest in another piece.
For a moment, he considers lashing out at her. Anthea would allow him to do so, not even meeting his eyes, but it would be an empty catharsis. He's not stupid, after all, and he can recognize moments when releasing emotion would be less helpful than maintaining calm. This is, he feels fairly sure, one of the latter moments. Probably.
—-
"DI Lestrade, how may I assist you?"
"Geoff, please, Mr. Holmes, and I think we've found something." The silver-haired man pulls up a still image lifted from the crime scene footage. "See that, there?" He points to a nearly imperceptible shadow in the lower right-hand corner.
"A footprint?"
"We think so, yeah. I've got Anderson down there taking photos, but I thought you'd want to see it yourself. It's none of us, the size and make are wrong, so it's either John, Sherlock, or—"
"Yes, quite." Mycroft stands and offers his hand to DI Lestrade. "Well done."
—-
It isn't Sherlock's shoeprint. Anyone with eyes would have known that, but Mycroft is too absorbed to give Anderson a stern lecture about doing his job, dammit, it is his job to not be an utter imbecile incapable of basic logic. Instead, Mycroft carefully thinks through the immediate answer he knows. This cannot be Sherlock's shoeprint for many reasons. Sherlock has long, bony feet with almost no arch. Mycroft has very clear memories of Sherlock's toes poking him in the sides, of Sherlock's moaning and groaning about finding long enough socks, of Sherlock padding downstairs in too-short pajama pants to shoot up in the garden. Besides, he would rather scald all the skin off his feet than wear the execrably common trainers that leave this distinct waffle pattern.
Dr. Watson, conceivably, would own a pair of these types of shoes. However, according to the file, Dr. Watson's feet are a bit too short and his arches a bit too high for this imprint. And although it is possible that the doctor would own trendy trainers, it is unlikely. Mycroft cannot recall ever having seen Dr. Watson in shoes other than near-Army regulation boots.
That leaves only one option: Moriarty, or someone with him. Sometimes the ways in which life imitated fiction made Mycroft almost giggle with glee. How silly, really, that a single, sooty shoeprint shielded from the flames by an errant piece of tile, might save Dr. Watson's life — and Sherlock's chance at becoming, as Anthea would say, "a real boy."