Vernon and Petunia Dursley retreated back into the connected bedroom following the explosions. Uncle Vernon was quite purple in the face, still grinding his jaw and muttering under his breath about "magic tricks" and "Better not come crawling back to us after that show". Neither of them, however, seemed keen to confront Hagrid again; it was clear they both thought that the sooner they rid themselves of their nephew, the better. Mycroft stayed behind, the lone spectator, and Sherlock impatiently bit back his most urgent questions, the ones about his mother and father and how they'd gotten themselves "blown up".
Sherlock unconsciously rubbed at the growing ache in his head—his scar, again, what did that mean, and wondered whether the explosion still rang in the ears of the others. Mycroft calmly surveyed them both, though his hand twitched slightly, and Sherlock thought he must be fighting the urge to brush the dust and plaster from his immaculate clothing. Hagrid's wrath had entirely dissipated with the departure of the Dursleys. With one hand each he had righted the sofa and lumpy armchair, apparently for the sake of something to do with them. Now he merely fidgeted, apparently uncertain how to continue the conversation.
Mycroft steered a shaken Sherlock to the armchair and perched, himself, on the foot of the bed. Hagrid took his cue and lowered his weight onto the ancient sofa, which promptly collapsed. Mycroft pretended not to notice. Sherlock actually didn't. He was still running through the most recent revelation in his head; Mycroft knew the signs. Zoning out, for Sherlock, was no more unusual than a flamingo standing on one leg.
But highly inconvenient just now, Mycroft thought, inhaling deeply. He had to have patience. Caution was necessary here if they were to avoid a repeat of…whatever had just happened.
"Perhaps you could start at the beginning, Mr. Hagrid? My cousin lacks the context to fully understand the, er, purpose of your visit."
The giant looked relieved.
"At the beginnin'. Righ'. 'Swhat Dumbledore said. Well, Mr. Potter, did yeh ever find tha' strange things start happenin', when yer scared or upset?"
There was a moment's silence before Sherlock shook himself back into the present.
"Once or twice," Sherlock said. It was fortunate that his eyes were locked on Hagrid as he said it. Mycroft was shaking with silent laughter behind his back.
"Tha' was magic. Yer a wizard, Sherlock."
The following conversation was enthrallment itself, even though both boys were doing their best not to cringe at the visitor's grammar. Hagrid explained about Hogwarts, Diagon Alley, Sherlock's school supplies, and the basics of magic. When the explanation wound down, Sherlock made an unexpected request.
"Do some magic," he said.
Hagrid was taken aback. "Do some…blimey, Sherlock, don' yeh believe me, after wha' yeh just did?"
Sherlock schooled his expression carefully.
"What I felt," he said, "was an explosion. Explosions can have any number of possible causes. That I was the catalyst of this one seems probable, but thus far you have offered me no evidence that Hogwarts school even exists."
"Or that magic can be controlled," put in Mycroft, amused.
Sherlock glared at him.
"Why are you still here?"
"My bedroom?"
"I didn't realize you were so enamored of it when we came."
"You're blocking the view," said Mycroft.
Sherlock determined to do what he did best, and ignore him.
Hagrid's hopes that the request had been forgotten were dashed when Sherlock turned back to him expectantly.
"Er…" he twisted the frilly pink umbrella in his thick fingers, avoiding Sherlock's eye. "It's just that, strictly speakin', I'm not surposed ter do magic…"
Mycroft interrupted smoothly. "Surely it would be permissible here. After all, you were sent to introduce magic to a boy who has grown up without it. There's no telling how difficult he'll be to convince."
Sherlock joined in, wearing an expression of skepticism. "I'm sorry, Hagrid. I really am. But you have to admit it sounds pretty unbelievable."
He stood, dusting bits of plaster off his jeans, and offered his hand to the flustered groundskeeper. "Thank you for your time, sir, I'll show you out."
To Mycroft's everlasting credit, he kept a completely straight face.
An hour later, the three of them were silently, and contentedly, finishing off the last of the sausages and rather squashed chocolate cake that Hagrid had brought forth from one of the pockets of his enormous coat.
"Fer yer' birthday, Sherlock," he had beamed. Sherlock was learning to read the expressions behind the dark, wild beard that covered most of Hagrid's face. "I owe you 'bout ten more o' these, mind yeh."
Sherlock couldn't keep himself from grinning. He'd never had even one.
The cake was dense and thickly chocolate; even Mycroft had a smear on his face by the time he had finished his chunk. The fat sausages gave off a wonderful crackling sound and a lovelier smell as they browned over the fire. The furious whispering from behind the door had broken off once the light began to flicker, and Aunt Petunia had opened the door just enough to beckon her son away from the unknown stranger. But Mycroft barely heeded her, caught up as he was in Hagrid's explanations.
In the early hours of the morning the three of them finally dropped off to sleep on their respective pieces of furniture. Sherlock, to ward off the chill from the window, was wrapped in the stranger's enormous moleskin coat, which covered him so completely that only a tuft of dark hair poked out.
Sherlock and Hagrid rose again at dawn, and Mycroft did the same, if only to see them off. While Hagrid was struggling back into his coat (a feat for which he was forced to bend almost sideways in the low-ceilinged room) Mycroft leaned against the splintering doorframe of the tiny bathroom. His expression was wistful.
"I must say, cousin, I'll miss the melodrama when you're gone to school."
"Ah oo ike atchyer ads ood eshur ise."
"What?"
Sherlock rinsed and spat into the grimy sink. "I said, I too enjoy watching your dad's blood pressure rise."
Mycroft glanced back at his parents' door. "Charming."
Sherlock grinned. "You never know. With me gone, he could fall below, oh, 180/120."
"I suppose that today as soon as I'm not around, you'll ask Hagrid about your parents?"
The grin vanished. "Obviously."
"Diagon Alley sounds quite…enchanting. I realize it's out of character, but try not to get too distracted by shiny objects." Mycroft's voice dropped for a moment. "I would like to know, as well. If you decide you don't mind telling me."
He sounded a little too sincere. Sherlock narrowed his eyes.
"Why would you care?"
"Lily was my aunt, you know."
"Oh, are we saying their names now? I thought that was taboo." Sherlock made no effort to hide his bitterness.
Mycroft shouldered past him and squeezed an impossibly even amount of toothpaste onto his own toothbrush.
"I don't actually think you—or your parents—are the root of all evil, you know. Or magic either," he added thoughtfully.
"Don't you?" Sherlock sounded genuinely surprised. For a moment the silence hovered halfway between awkward and comfortable.
Then Sherlock, with characteristic mercuriality, spat the words at his cousin. "Did you know?"
"No, Sherlock. I promise."
Sherlock knew very well that Mycroft's promises were worth exactly the measure of inconvenience it would cause him to break them.
"Lies have tells," he growled, believing him anyway. "Uncle Vernon's rubbish at hiding them…I should have known it wasn't true—you definitely should have known…"
"You were perhaps four when you asked the question," Mycroft replied smoothly through a mouthful of toothpaste. (Sherlock would've given his stolen chemistry textbook to know how he managed that.) "I was six. Probably at school at the time."
"You remember."
"I recall the dust-up at dinner that evening on the subject of flying motorcycles," returned Mycroft drily. "It tends to stick in the memory."