Note: Thank you very much for your lovely feedback! Hope you're enjoying the mystery – here are some more important - possibly the most important - puzzle pieces! As always (I mean, this time especially, but really: Always), I am very interested in reading what you think :)

Warning: I know it's all over the story basically, but have an emphatic warning for child abuse in this chapter. That family…

Blackpool, Part 4/6

Even their parents flee Grimmauld Place occasionally. In the morning, Walburga dons an enormous veiled hat and Orion, a set of plum velvet dress robes with matching cane, and they set off for the 61st Somerset All-Day Thestral Race, leaving behind a quickly forgotten lecture and finally, blessed silence.

Of course, Sirius is busy. Four times so far Regulus has knocked on his door, trying to get him to come explore the attic, or play Vertical Quidditch, or even just go for a run in Regent's Park, because he feels that, with the summer progressing the way it does, his endurance now rather resembles that of an eighty-year-old, asthmatic chain-smoker. But every time, Sirius has been pouring over his altered diary, scrutinising every single page , match them to his memory, and coax the ink traces back into what they were before Walburga got her hands on them. Around lunch, Regulus gives up on him. Typical, thinks Regulus. It seems that when he told his brother to wait with the diary until he's less angry, he only succeeded in unleashing an obsessive-compulsive – albeit even-tempered - beast.

Now even this blissfully silent day is drawing to an end and Regulus is still sitting on the stone steps that lead out into their overgrown garden, reading. Next to him is a glass of Kreacher's home-made lemonade and a by now seriously depleted plate of biscuits.

The garden is a small affair, at least in the two dimensions that ordinary people would consider most relevant, a sickly oak tree overshadowing the unkempt lawn. Additionally, the garden is high. It ends more or less with the roof line of 12 Grimmauld Place, but it's compressed to contain almost half a mile of vertical airspace. The long shadows break oddly with the folded-over dimensions.

Regulus is almost three chapters into a book he liberated from the library – a beaten tome, heavily perused over the years -, when a large duffel bag is dropped next to him.

"Whatcha reading?" says his brother. "Pensieves and the Magic of Memories? No coincidences on god's green earth, I guess."

Regulus looks his brother up and down. The boy seems pale and distracted and obviously in need of a good dose of sunlight. Regulus takes a meaningful glance at his watch, which says it's gone six. "Do not ever," he says, "call me indoorsy again. You look like something that grows in the cellar!"

Sirius grins. "Break's over, nerd," he says. "We're playing Quidditch."

"All done with your diary?" says Regulus, turning another page on the Obliviate charm.

"Oh, yes."

"Could you turn it all back?"

"Better." Sirius grins widely. It's a tad disconcerting. "Will Kreacher be able to see us?"

"I asked him to make Beef Wellington for supper," says Regulus, feeling slightly guilty even as his eyes are scanning the last half paragraph of the chapter. "He'll be in the kitchen for ages."

They're not really supposed to be playing Vertical Quidditch in the garden, because its odd physics mean there's a drifting wormhole somewhere outside their parents' bedroom. But no-one has vanished into it since the late 1800s.

Sirius is halfway through putting on his gear when Regulus makes an executive decision. "We're switching positions," he says.

"Why," says Sirius. "Feel like hitting things?"

"My team's having to train up two new Beaters this coming year," says Regulus. "I'm not helping you get even better on your position."

"Regulus, you absolute Slytherin," says Sirius. "You're a shite Beater, though, sure you're up to this?"

"So? You're an absolutely appalling Seeker," says Regulus. "Come on up. First one through the wormhole gets a surprise trip to the Palaeolithic."

"Oh, all right," says Sirius. "But dibs on your broom."

Regulus's broom is sleek, flexible, and fast, and seeing it respond to Sirius without a hitch almost makes Regulus regret he suggested this. Sirius's broom is a warhorse, designed to withstand heavy forces – but all the collisions mean the steering needs frequent recalibrations, and Sirius obviously slacks off on that over the summer.

On the other hand, Regulus does feel like hitting things.

The Snitch zooms off as soon as it's released and Sirius is after it in a heartbeat, rising high above the oak tree. Regulus sends the Bludger in his brother's general direction, then kicks off himself, keeping an eye out for the Snitch, out of habit – but it's properly vanished for now.

Vertical Quidditch means they're spending a lot more time than usual in descends and steep climbs. Grimmauld Place's garden is not evenly stretched – it's a number of overlapping spells, and the result is somewhat patchy. Once, Regulus hits the Bludger towards his brother – his entire body reverberating from the impact – and it comes straight back at him a second later. Only quick reflexes save him from being knocked off his broom, the Bludger skidding over his side. That'll be a bruise, he thinks.

"You all right?" shouts his brother. He's a bit roughed up by the Bludger himself.

Regulus laughs. "Any luck with that Snitch?"

"It keeps… slipping away…" comes Sirius's frustrated voice as he makes another attempt grabbing the glittering Snitch floating a few feet below him. It ambles off and flutters. Like it's laughing.

Regulus rises a few feet to meet his brother.

"That's because you slow down like a moron when you see it hovering," he says. "It predicts the broom's movements. Something with the vibrations. Either go faster than it, or don't move at all."

"What, you just hang around and wait for it to drop by?" says Sirius sceptically.

"No, you just have to… surprise it -"

The Snitch is hovering about four feet below them, with the highest branches of the oak tree another two hundred below it. Regulus considers the situation, then lets himself fall swiftly sideways, one knee hooked around his stationary broom. Upside down, his outstretched hand plucks the Snitch from the air, wings fluttering against his gloved palms, like a tiny heart.

"Like this," he says, unable to keep the smugness out of his voice even as the blood is rushing into his head. Sirius drops a few feet to be level with his head

"I forgot," he says. "Broomsticks, monkey bars, same thing to a Seek- duck!"

The forgotten Bludger zooms past where Regulus's head would have been, had Sirius not grabbed him by the shoulder and swung him out of the way. A second later, Regulus oscillates back into its path and gives it a good hit with his bat. The Bludger flies off into the dusk, laying low for the time being.

Sirius looks him up and down. Or down and up.

"Duck?" says Regulus.

"It's a reflex," says Sirius. "I don't know what the upside down equivalent of ducking is! So what's your deal, Reggie?"

The world looks different from this perspective, and Regulus ponders his brother's words. "…Which one are you referring to?"

"The deal where you're afraid of your own shadow, but apparently gymnastics on a broomstick two hundred feet up in the air are okay?" says Sirius. "Not judging, mind."

Regulus laughs, freely and, for the first time this summer, without worrying who might hear. "Oh, that deal," he says. "I just like flying."

Getting a tiny bit tired of hanging upside down, he says, "Hold these," and hands his brother the bat and the struggling snitch before swinging himself back to a more conventional sitting position. "One more?"

Sirius grins at him. "One?" He throws the Snitch up in the air.

An hour later, his brother has started to get the hang out of this Seeking business. If Sirius weren't drawn to the Beater's position so much – hitting things with bats; it's like the position was invented for Sirius – Regulus supposes he would make a fine Seeker, or at least an enthusiastic one – what with the ludicrous speeds, the absolute focus, the almost intimate rivalry with the other team's Seeker, the insignificance of things such as Bludgers or goals or survival.

He's oddly surprised that he's starting to warm up to the Beater's position himself. There's something to be said about hitting things – the jolt goes through his entire body every time, and a pleasant, warm sort of fatigue is starting to settle in his muscles. His hair is slick with sweat in the dying sunlight, his hands are developing blisters from the thickly padded, inflexible Beater's gloves, and his wrists are starting to hurt, but despite all, he's starting to have fun.

Sirius catches the Snitch three more times – once by plucking it from the branches of the oak tree, once from mid-air when it daringly tries to zoom past his ear, and once from a spectacular, possibly wormhole-enhanced Wronski-esque feint. His other eleven attempts are foiled by Regulus and his increasingly well-aimed Bludgers, nearly knocking his brother off his broom.

But now they're at an impasse. The Snitch, starting to get tired, is hovering near the upper end of their garden, almost half a mile off the ground. Sirius is trying to get at it, but Regulus has inserted himself between his brother and the Snitch, laughing himself silly. Every time one of the brooms manoeuvres, the Snitch flutters off another two feet.

"Tie?" Regulus suggests.

Sirius gives him a bright-eyed and somewhat deranged look. "Never!"

There isn't even time enough to call Sirius an idiot. For his brother throws himself off his broom – which, without a rider, is already descending gracefully downwards - and leaps onto Regulus's, hanging off the handle by the fingertips of his left hands. Swinging wildly with his legs, he gains momentum, rocking the broom this way and that, and then –

"Got it," he shouts.

"Still a tie."

"Watch and learn, amateur," comes the slightly out-of-breath reply.

Regulus gives it a good long pause. "Comfortable?" he inquires. Eventually.

"Now that you say it," says Sirius from below, "I would appreciate a hand."

Regulus can't help but laugh as he reaches down. "You know," he says, "I'm fairly sure you're supposed to finish the game on the same broom you started on."

It's a bit of a scramble, since Sirius is not letting go of the Snitch – but with a lot of tugging, and shoving, and pulling, and kicking, he finally settles in behind Regulus on the broom.

"I'm starting to see why," says Sirius. "Bit crowded, isn't it?"

"All right," says Regulus. "I'll bring us –"

Wham!

The forgotten Bludger hits the front of the broom straight on, sending it into a wild spiral down the stretched, bumpy gravity of the garden. Regulus reacts instinctively. Unfortunately, so does his brother.

"No steering from the passenger seat!" yelps Regulus –

"It's my broom, you –"

"Shut up and hold on!"

"- need to lean the other way –"

- and after another twenty seconds of feeling like he's stuck in the world's worst roller coaster, Regulus finally has the stubborn broom back under his control.

"Merlin, what did you do to that broom?" he says, breathing against the panic that is finally making an appearance. This far from sea-level, it subsides quickly.

"I was deflecting Bludgers at you for six bloody hours that last match, that's what I did to the bloody broom!" says Sirius. "Couldn't have caught that Snitch any earlier, could you?"

"I wanted to," says Regulus, "except I was being pelted with Bludgers for six hours –"

He realises he's laughing again. Sirius, meanwhile, retrieves his wand from his sleeve, and sends the Bludger floating gently to the ground half a mile below, harmless as anything.

"Well, as I was saying…" says Regulus, "hold on, I'm bringing us down."

"In a minute," says Sirius.

This most recent collision seems to have thrown off the broom's steering completely. As a result, the broom is swaying drunkenly even now that it's stationary. Sirius is holding on to him with one arm, the other still closed around the fluttering Snitch, and if Regulus didn't know any better, he'd think his brother just needs to catch his breath.

"I was thinking," says Sirius. "No portraits up here. No house-elves. No garden gnomes. No –"

Translation: No-one to spy on them. Ingenious. Potentially premeditated. Sirius would have done all right in Slytherin, Regulus supposes.

"Got a confession to make?" says Regulus.

"More of an apology," says Sirius into his ear. "Or, well. A warning."

Despite all, he's still almost whispering. Regulus has to strain to hear him over the wind. Sirius's arm is wrapped tightly around Regulus, sweaty hair tickling his own. It's close in a way Regulus usually minds a lot; in fact, his brother is the only – and currently slightly dubious, what with the sweat and all – exception to that.

"I'm listening," says Regulus. Already he feels like the fun part is over, and they haven't even touched ground.

Sirius takes a deep breath. "Whatever goes down tomorrow," he says very, very softly, "you stay out of it."

Uh-oh.

"That sounds ominous," says Regulus. "What –"

"Promise."

Regulus stays still for a long time, his brother's breath close to his ear. And since this is exactly his area of expertise, he realises Sirius is scared.

"You're going to pick a fight," says Regulus.

"Promise."

"About the diary," he adds.

"Promise."

"Don't."

"Promise you'll stay out of it," says Sirius.

Suddenly, Regulus is angry. "I wasn't going to get into it!" he says. "Sirius, you know exactly what's going to happen."

"…Yes," admits Sirius.

"This time tomorrow, I'm going to tell you I told you so," says Regulus. "Because it's going to be your fault. You should know how to handle them by now, and yet you absolutely refuse to stay out of trouble – you're inviting it – you deserve it, you bloody Gryffindor wanker."

His brother stays silent for another long while. "As long as you stay out of it," he says eventually.

No longer able to tolerate this nonsense, Regulus concentrates on manoeuvring them both downwards. The landing, despite his anger and the shot steering, is soft as butter. He leaps off the broom as soon as they touch down and whips around.

"Then what was this about?" he says. "Saying goodbye?"

The dusky sky has long-since turned indigo. "I don't do goodbyes," says Sirius.

He settles into the overgrown grass, slotting the still-struggling Snitch back into its case, and sealing it for next time. If there is one. Then he carefully tugs Regulus's tight Seeker's gloves off his hands. The expression on his face is something new, too:

Sad. Scared. Determined.

Regulus fights down the urge to ask him why. What's happened this time to morph his particular brand of chaos from "spontaneous" to "premediated". Because the truth is, Regulus is scared too: That he will agree. That this will spurn his brother on. That it'll make everything so, so much worse.

"I can't do this without you," Regulus says. With a feeling he's going to regret this either way, he turns his back on his brother and steps inside.

Twelve hours until the explosion.

The explosion is heralded by shouting.

For the most part, it sounds like one of their usual rows – in fact, they're probably overdue one, this late in the summer. By the time Regulus notices anything unusual, they're really in full swing, Walburga and Sirius. Shreds of "impertinent" and "freak" and "you will regret this" rise above the general wall of noise as Regulus tiptoes towards its source, determined he's going to stay out of this – but also feeling that this is something he should not be missing. He's missing so many things already.

"You horrible child – how dare you talk to me like that – your own mother –"

Walburga has a good yelling voice, shrill, piercing the walls of Grimmauld Place, and somehow still articulate, but Sirius's has grown to match hers. At fourteen, almost fifteen, he's almost done sailing through his voice change, and it's already as deep as their father's, but far less controlled, and just unbelievably loud, and it's four more years of this and already Regulus is fearing for his sanity.

And his ear-drums.

"You're a liar," shouts Sirius. "You're a perverter of language, you're a spider in a web –" and that is new, too. Usually he is reactive – maybe overreactive, but rarely accusatory. Maybe because he's not actually suicidal.

Not usually, at least.

Regulus peers around the corner into the drawing room. Sirius is backed up against the wall. He's without his wand; instead, he's clutching his diary protectively against his chest.

Unbidden, Regulus thinks of all those wonderful maps, those detailed drawings that Sirius has just managed to put right again, and for some reason that's what's making him shiver, not the shouting, not the way Sirius is trapped without escape, no: Walburga has an uncanny sense for her sons' weak spots, and Sirius is presenting his on a silver platter.

"You have spoken to that wretched girl," she yells, "that Mudblood courtesan that fills your head with lies and fancies, you'll end up like her, mark my words –" Behind Sirius, the tapestry quivers in anticipation.

"Then tell me, Mother!" shouts Sirius. "If it didn't happen, why can I see Thestrals?"

"You never saw a Thestral in your life, impudent boy!" screeches Walburga, too agitated to make anything up on the spot, her carved oak wand twitching in her hand. "You boast, you saw a picture in a book!"

"You're a liar and a m–"

Regulus wishes Walburga had less impeccable timing, because Sirius's voice dies away at the brink of something quite possibly world-shattering. His face twists into expressions of surprise, annoyance, and finally, horror. He's gasping for air, and it takes Regulus a moment to figure out why: Sirius's clothes are constricting around him, a million fibres tightening to squeeze his skin, fine linen and wool becoming as stiff and unyielding as leather, or steel. His arms snap to his sides, rigid, shaking.

The diary falls from his hands.

"What did you call me?" says Walburga.

But Sirius is wheezing, like he's breathing through a tiny straw. His chest can't expand against the straightjacket that was formerly a loose white shirt. There is simply not enough air for him to talk.

Walburga strides forward, hand raised - but this time, hitting won't do. Her wand slashes through the air, and whatever it does, it makes Sirius double over as far as his treacherous clothes will let him, eyes widening in pain and rising panic. For one terrifying second, they lock with Regulus's, still in the doorway – but then Sirius looks away before their mother can catch on.

"What did you call me?"

Sirius's lips move without sound, but Regulus can't look, he can't, because if he does, if he understands this - and already it's on the brink of his memories, drowning, drowning, drowned – he wrestles it down, holds it under -

Whatever she did, Walburga lifts her wand to do it again.

Oh, Regulus wishes he were brave. He wishes he could move, hurl himself between his brother and that curse – just as his brother would surely barrel forward, not press himself into the doorframe, trying hard to look like wood –

And then –

No, he thinks. No no no -

The diary has fallen face-up, and from it rises the ghost child, hovering in front of Sirius, almost a head shorter than him but making up for it by floating. The ghost whirls around to face Walburga, but something's different about him:

He's not blurry at all. His image is crisp as a photograph, from his wispy dark hair to his small leather shoes. Regulus can't look away, not from those long-lashed bright eyes, that pouting child's mouth – the ghost's little face is impossibly, painfully familiar, like a nightmare that his brain refuses to revisit – no, not a nightmare: A memory –

The moment passes. "You leave him alone!" the ghost shouts. "Sirius-like-the-star is a good boy, you leave him alone, you horrible old hag!"

Predictably, he starts blubbering again. Still. Had Regulus thought the ghost didn't evolve? He used to be so scared of adults he would dissolve at the sight of them. The ghost is wailing now, but he perseveres, shielding Sirius with his immaterial body, for all the good it will do.

The spell that has kept Sirius trapped is faltering in the face of this new development, and Sirius draws wheezing breaths, carves a word into the shaky exhale, "Run - "

Which is when Regulus realises he should have paid attention to his mother all along.

Walburga Black looks, for lack of a better expression, like she's seen a ghost. Granted, not for long – her brain can't handle shock, or shame, or loss of control, it will simply snap back to whatever it was doing before. She looks from Sirius to the ghost to the diary and back, and Regulus can see her draw the connection.

"You brought a ghost into this house," she says softly. "After all our efforts… all the wards… only ghost-free Georgian townhouse in all of England… and you bring home this. This abomination, this dead thing that couldn't even die properly – but how -"

"How not," Sirius says, voice still less than a whisper. Regulus sees his brother's collar squeezing into the soft skin of his neck and dimly notes he's starting to hyperventilate in sympathy.

"The water?" says Walburga. "Oh, for all your faults, why couldn't you have been more of an idiot." The way she says it, it still sounds like an insult.

Sirius, despite himself, grins. Briefly.

Walburga grins back.

"Good boy," she says. "Tied it to an object. Easier to clean up."

All traces of Sirius's smile vanish when the diary at his feet bursts into flame, ignited by a cruel flick of his mother's wand. Instead, his face now looks old – resigned, rather, like he never expected anything else to happen to his diary, intricate maps, complex layered spellwork, drawings of all his friends, all the love and care and memories he's poured into it: Heat and smoke and ash.

The ghost, panicked, turns to him. He's already fading.

With great effort for such a minuscule movement, Sirius holds out his hand. "Imagine," he whispers, and the ghost takes his hand, and for a moment Regulus thinks, maybe –

Maybe -

The ghost flickers out of existence.

Regulus remembers the letter his mother wrote after his Sorting. Fire burns hot, but it can be smothered. Water does not compromise. A lie then, or maybe a truth she doesn't care about, because truth is what she creates, and right here, it's Sirius's memories burning up before his eyes, his hand still held out to a long-dead child.

"How could you," Sirius whispers.

"What do you call me?" says Walburga.

"A m-," says Sirius. "A m-"

"What do you call me, Sirius?"

"A mother," Sirius enunciates with great effort. His lips are tinged blue. "You're a mother."

His clothes relax, but they're damaged, hanging rumpled and shapeless off his frame. Sirius himself is sort of just hanging there, arms and legs and shoulders and head, held up only by spine and spite, and finally, he draws deep, gulping breaths.

"You wait in your father's study until he returns," says Walburga.

Regulus flees from the premises before she turns and sees him, too.

The brutal oak door of Orion's study fills Regulus's entire field of vision as he studies it carefully, trying to find some clue in that ancient wood. Just one reason why he should not knock.

But the wood is unhelpful, and Regulus raises his hand, raps his knuckles against the door, trying desperately not to be heard. For a tense, merciful second, everything remains silent.

Then his father's cool, impassible voice sounds through the door. "Enter."

Regulus enters quietly, somehow still hoping he might not be noticed. Silly.

The house may be Georgian on the outside – but inside, it can be much, much older. Orion's study is marble columns and gathered curtains; a square of Ancient Rome in the middle of London. It's quiet, though, and dark – the study faces north, like Regulus's own room, and it's just drab Grimmauld Place outside, not the Forum Romanum.

Sirius is sitting at the desk, writing carefully in a book. Orion, meanwhile, is waiting by the window.

It is not at all what Regulus has thought it would be like – what Sirius has, in fact, described over and over in his diary, in those long passages that Regulus would glance over because he couldn't bear it, and what is now finally exposed as the embellished lie it is, because Sirius is just doing lines. Right?

"Yes?" says Orion? "What is it?"

He looks from Sirius to Regulus and back again, like he's trying to determine whether he's got the wrong brother. Regulus is dimly aware that other families may have fathers who are able to tell their children apart – but he pushes that thought away.

"Mother sent me," he half-whispers, but in the quiet of the study, he might as well have yelled.

Again, his father's gaze slip to Sirius, and then back.

"To witness," Regulus clarifies hastily. "She said it was to be a lesson."

"Ah," says Orion. He looks thoughtful. "What do you think, Sirius?"

Sirius barely looks up, like Regulus is some sort of annoyance. "A lesson?" he says. His voice has mostly recovered, though there's still a hoarse undertone, like he just got over a bad cold.

Orion shrugs. "Your mother seems to think so."

"Oh, I'm sure it will be," says Sirius, his quill still moving over the parchment. There's an undertone in there that Orion chooses to ignore. Instead, he waves Regulus over to an armchair by the door, a not-so-safe distance away.

"Of course," muses Orion. "We've had some trouble with our previous lessons, haven't we? Perhaps you are hopeless, but your brother –"

Sirius's quill stills over the parchment.

"One of you will learn from this, I'm sure," says Orion. "Let's see what you've got."

He snatches the book from Sirius's hands and turns back to the window to read. In that moment, Sirius catches Regulus's eyes again, and raises a hand to his lips, making an unmistakeable zipping motion.

Regulus hadn't planned on speaking up, but it's nice to have the endorsement, he supposes.

By the window, Orion sighs audibly, then steps over to pick up an ornate quill from his desk. As he sets down the book, Regulus can see it's filled with paragraphs of dense writing.

"Seems like we have to try again, do we?" says Orion. "Reason you've been sent here, it says –"

"Talking back to Mother," says Sirius.

"Yes, I can see you have detailed the backs and forths of that conversation. And do work on your punctuation," says Orion with a certain amount of distraction as he bends over the words in front of him. He crosses out the text with deft strokes of his quill, and scratches a single word underneath.

"You're here for telling lies, Sirius."

"I didn't –"

"It really is as simple as this."

Sirius looks like he wants to talk back, but remnants of self-preservation come through.

"Suggested punishment…" continues Orion. "You wrote six. Why six, Sirius?"

"Nice friendly number." Sirius shrugs, and his shoulders are shaking but his voice is not. "Six days before I can go back to Hogwarts."

"Oh, we'll see about that," says Orion. "How about twelve? After all, there's two of you. Six more days to poison your brother's mind."

Sirius flinches when his father says twelve. Still, he sounds bored when he says, "Twelve is… rather a lot, don't you think?"

"True," says Orion. "Maybe split? Six each? Make sure the lesson really sinks in for both of you?"

Each?

Regulus knows he should be scared, at least as scared as Sirius looks, but mostly he is just confused.

Sirius looks at him, and then he looks away like the very sight is overwhelming. "Twelve," he says, and this time, his voice nearly breaks.

Orion, on the other hand, sounds almost bored. "Tell you what, we'll make it thirteen," he says. "For being an insufferable Gryffindor."

There's a blink, a pause, and -

"Fourteen."

It's unclear who is more shocked, Orion – or Sirius himself. But really, how neither of them could see this coming… because, Regulus thinks, this is exactly how you rile up Sirius Black.

"Fourteen," Sirius repeats. "And you send Regulus out of the room."

"Fifteen," says Orion. "For haggling like a commoner."

An unbidden memory comes up, and Regulus can't push it back anymore: That first Christmas after Sirius's Sorting. How his brother hadn't left his bed for two days. What he wrote in the diary. Lies, Regulus tells himself. Sirius embellishes, even his friends say so. He has a flair for dramatics, for stories, for lies -

"Please, Father," Regulus starts, not knowing why this is the moment he chooses to speak up, not even knowing what he's going to say, maybe six each sounds fair, maybe please send me away like he said, but he doesn't even get that far.

"Sixteen," says Orion. "You both need to learn a lesson about talking back."

I thought it was about telling lies, thinks Regulus, and bites his tongue. He's sure he looks wretched enough, wants to apologise to Sirius, too, for earning him one more of whatever it is Sirius is so scared of, but -

"Regulus," says his father. "Go and get me number three."

Regulus gets the distinct impression he's supposed to know what's meant by that, but he doesn't. His mind is dangerously blank. The knowledge just out of reach, he knows that much, but it might just as well be miles away.

"By the fireplace," says Sirius.

So they're both in on the joke and Regulus isn't – but of course, it's not a joke.

It's a ritual.

It's a terrible ritual that only repeats and repeats. Like any ritual it requires play-acting, and that's how Regulus makes his way over to the fireplace; he acts the obedient son while his heart is digging itself right out of his chest. His throat is constricted with a terrible pressure, and he prays he may faint, or maybe just explode, yes, just go supernova, burn up white-hot and angry and obliterate all, this room, this god-forsaken house, this forlorn planet and the cruel curse of humankind.

If only.

Three long wooden rods are leaning against the mantlepiece. Which one's number three, anyway? Resisting a sudden urge to go Eeny meeny miny moe, he picks up the one on the right, and a jolt goes through him, a flash of intense, raw feeling – unworthiness. Guilt. A disquieting bout of nausea. And on top of it all: Anger. So much anger.

"Hold it by the handle, boy," comes his father's cool voice, addled by just a hint of impatience.

Ah. The handle is just a knobbly bit at the end, dyed a subtly darker brown and densely covered in runes that Regulus now realises are protecting the holder. Even then, the thing leaks dark, tender energy into him, suggesting the wood, not unlike a wand, holds a magical core: Spun silk from an Acromantula, or a sinew from a Thestral.

Holloway rods, his memory supplies.

He's read about them, in library books he wasn't supposed to borrow except Slughorn signs off on exception after exception. It occurs to Regulus, not for the first time, that his father does not own all these dark artefacts, no: They own him. Things like the Holloway rods are never content leaning against the mantlepiece; they demand to be used. They feed on darkness, all the time. They soak up pain and fear and suffering and keep them for later. And every single one of those books have warned Regulus not to stick around for that.

It's daring, mad, irresponsible – and Regulus supposes it answers the ongoing mystery of where Sirius got it from.

He has half a mind to chuck the thing into the fireplace. But that won't even singe it, and he must really not dawdle a second longer -

When he goes to hand it over to his father, Orion pauses before taking it, his hand so close Regulus can feel its warmth on his own.

"Would you like to do the honours?" Orion inquires.

Somewhere in the shallows of Regulus's mind, he hears the rhythmic surf of the sea, and that's usually an indicator that he's going to spend the rest of the day in quite a state. He therefore doesn't manage his usual levels of diplomacy.

Or any diplomacy.

"No!" he yelps. His brother snorts softly, almost inaudibly, but it's still registered by their father, stored away for later.

"I see," says Orion. "Tell me, is that because you're weak? Or because you think it's wrong?"

What in blazes could possibly be the correct answer to this? Desperately, Regulus looks at his brother, who makes a complicated hand gesture behind their father's back. Unfortunately, neither of them is particularly adept at impromptu sign language.

Okay. Deep breaths. After all, he did lecture his brother on how to handle their parents just the other day. "I just don't think it's appropriate," he says. "I'm the younger, after all."

Orion shrugs, as if he really doesn't care either way, and directs him to sit on that dreadful armchair, to watch.

Regulus hates his father in that moment for making him complicit, hates his brother for his temper, hates himself for aiding this ritual, this pointless theatre, ostensibly to get Sirius back on track, effectively running him off. If he were any braver, he would walk out.

If he were any braver, he might be in Sirius's place.

He wills that armchair to eat him, those cool, dark shadows to swallow him up – or else he wills himself to become part of them, a silent, unfeeling part of the scenery. He feels so much he may yet explode.

His brother doesn't need instructions. Sirius rises from his chair to stand in the middle of the study he is going to inherit one day, opening the buttons on his shirt, that same one that tried to strangle him earlier. He shrugs the shirt off, folds it carefully – then lets it drop to the marble floor, as if daring Orion to up the ante.

No reaction from their father, so Sirius steps forward, places his hands on either side of the marble column rising in the middle of the room, and with a distant, crackling, ancient sound, his hands turn to marble, too, fusing with the cool, smooth stone.

Some part of Regulus dimply appreciates how extraordinary this magic is, automated human transfiguration, bound to a room – but then Orion says, "Ready." It's not a question.

Sirius's voice is steady, too, if softer than usual. "Sixteen," he says.

Regulus has sort of kept the panic at bay until now, but this is it, the waters are rushing in, his breath is taking on a life on his own – and he welcomes it, makes it easier to ignore, ignore, ignore what's happening no ten feet away -

"Fifteen," says Sirius, his voice catching on a hidden snag. This time, the rod comes down in the space between two heaving breaths, Regulus hears it and not even his terrible memory will ever make him forget that sound, a snicker, a rush, a whisper of darkness from that infernal artefact.

Like it's feeding.

Like it's alive.

A minuscule pause, and Sirius says, "Fourteen." Regulus can't help it, his hands fly to his ears, too little, too late. He's definitely drowning now, fidgeting, splashing, flailing, obvious.

"Thirteen."

But nothing.

"Wait," says Orion, and he's stepping forward. Regulus barely registers that his father is coming for him now before Orion takes his face in his hands – and he so rarely touches Regulus at all – and says, "I didn't say to watch your shoes."

Regulus nods mutely, trying to shrink away from those hands – that darkness is leaking, it's going to be all over him in a minute –

Orion sighs, a prim little sound of disappointment. "How old are you again, boy?"

"Thirteen," whispers Regulus, his eyes fixed on the Holloway rod that is, for now, leaning against the desk, twitching with impatience.

"Thirteen," repeats Orion. "I daresay that's old enough. Your brother has been coming here since he was six."

"I know," says Regulus, and not to his father. "I'm sorry."

"It's not your fault your mother is soft on you," says Orion, oddly gentle, before he returns to the task at hand.

It takes an agonisingly long time. A quarter hour ticks by on the grandfather clock and they still aren't done here. They keep waiting for Sirius to regain his voice so he can continue the countdown. They keep waiting for Regulus to take deep breaths and look up from the floor. When they reach a croaked, "Five," Orion takes a break, has Kreacher bring up coffee, offers Regulus a biscuit that he refuses. The house-elf shuffles and lingers.

It's just so needlessly archaic, thinks Regulus, in the space between strokes when he can almost think, it's archaic and pointless and doesn't achieve anything except misery, this-hurts-me-more-than-it-does-you, it certainly hurts Regulus more than it does his father, because it's clear that Orion doesn't understand pain at all, judging by the indifference with which he dishes it out.

It's equally clear that Sirius does, he's trapped and shattered and eaten by pain, pressed up against the marble like he may turn into a statue altogether, hide inside an Ovidean metamorphosis. If only it worked that way.

And then they get to, "One," a half whisper, half sob, a last slash of the hungry Holloway rod, thank god this is over –

But it's not.

The spell that fused Sirius to the marble column breaks, and his hands fall to hang limply by his side.

"What did you learn?" says Orion, his tone almost friendly. "What was today's lesson?"

"No more lies," says Sirius. His voice is hoarse and broken.

"Good boy."

But Sirius's shoulders are heaving, and it takes Regulus a breathless second to realise is brother is laughing. At first Regulus thinks it's just relief, but it's not. Then he thinks it's a calculated provocation, because Orion can't stand not being taken seriously in the middle of a powerplay – but it's not. Finally he thinks it's a Black thing, this disposition towards inappropriate emotional responses.

One unfortunate truth about the Black family: Just because something is hereditary doesn't mean it's going to fly.

"Any questions?" says Orion, and he no longer sounds friendly.

"One," says Sirius, when he has his voice under control. "Just the one. Why can I see Thestrals?"

And it quickly becomes clear why Orion Black usually keeps his control in such a tight grip: Because it takes him exactly ten seconds, as doled out by the grandfather clock, to lose it completely. Forgotten are numbers and marble columns, forgotten is all ritual, replaced by consuming, violent rage.

He is his wife's cousin, after all.

Forgotten, too, is Regulus, who bolts out of the door to do the one thing that might realistically save his brother now, which is to find their mother, and get her to intervene –

It would be impossible at any other time. But this is it, the rare moment she loves Sirius unconditionally: When he is broken on the floor.

It smells burnt in the hall, and it's coming from Sirius's room.

Regulus hasn't dared going over before, but now the chronically nocturnal household – yellow light from the front room, piano music from the gramophone, their parents talking, yelling, smashing glasses; silence, pacing, closing doors - has finally quieted down. Sirius's bedroom door is locked with but the weakest of spells, which by his standards is practically an invitation. Still, Regulus spends a full twenty minutes ruminating, torn between ignoring the weird smell and being annoyed he can't identify it, before a flick of his wand springs the lock open.

"Sirius?" he whispers into the darkness. He can't hear a thing, or rather, he can, but all the sounds are outside sounds – faint draught from the open window, distant white noise of Muggle traffic, a group of happy drunks a few streets over. Other than that, there's nothing, not even a breath, or a groan, or a sob. When his eyes adjust to the weak light of the streetlamps outside, he realises the bed is empty. Rumpled, but empty.

Oh, god, he thinks, they've done it, they've gone and killed him. The thought would seem ludicrous in daylight, but he's had half a night to make himself sick with worry. Or maybe, he thinks, they've gone and driven Sirius away, and he's abseiled through the window and wandered off into Muggle London, where perverts and thugs await, or so say their parents.

Then there is a sound, he almost misses it, like something tiny catching fire. An orange dot glimmers on the edge of his vision, and a shadow shaped like Sirius just tilts into view, like one of those images that are both a young lady and an old hag, he is both there and not there, sits very still in the frame of the bay window, legs drawn up and hugged to his chest, the cigarette between his lips just barely illuminating his profile.

There's about a hundred things Regulus means to say, has in fact rehearsed over and over. Naturally, the first thing that comes out is, "You idiot!"

As if Sirius weren't in enough trouble already without the entire storey smelling like a Muggle pub.

Bright eyes dart over to him, just a brief touch of attention, before Sirius is back to watching something fascinating outside. Around his bare shoulders, a blanket billows as if underwater. In all likelihood, he's enchanted it to weigh nothing, to keep it off the skin on his back.

Well, shit.

"Are you okay?" Regulus says, not caring how ridiculous the question is.

He starts thinking he's going to stand here all night, asking questions into the void while Sirius stares mutely into the same, but suddenly there's laughter. It's the same inappropriate laughter as before, only attenuated, like it's been smothered. A pillow to the face of an unruly child.

"Have you come to tell me I told you so?" says Sirius.

Regulus shakes his head.

"Well, you did tell me so," says Sirius. "Said I was inviting trouble. Said I deserved it."

"I didn't mean this," snaps Regulus.

There are very few surfaces in Sirius's bedroom Regulus would trust to sit on, so he tiptoes forward until he hits the edge of the bed, then perches down on the mattress.

"I've come to tell you I'm sorry," he says. "About the diary. And the ghost."

Sirius huffs. "You hated the ghost."

"I didn't," says Regulus. "I found him annoying. And I'm still sorry he's gone. Is he really –"

He wants to say dead, but he's sure that's not the right word.

"He's tied to the diary," says Sirius, and he laughs again, and this time it's brighter. "Nobody said it had to be whole, though."

His hand reaches between the inner and outer window pane, where it emerges with a square piece of parchment.

"Andromeda meant it when she said the diary would never run out of pages," he says. "Boy, there were so many."

"Oh god," says Regulus. "Oh god. How many –"

"I hid them," says Sirius.

"Where?"

"Everywhere."

"The drawing room?"

"Everywhere."

"My room?"

"Everywhere, Reg," says Sirius. "I love that bloody ghost, and he's not going to get banished. Not on my watch."

"They're going to kill you," whispers Regulus, and still - maybe because he's tired, maybe he's panicking - it does not feel like hyperbole. "Tell me where you put them, Sirius," he says. "I'll collect them and we bring them to Hogwarts, he can stay there, it's safe, but this is – this is insane. You're insane."

Sirius looks at him like he's the one being unreasonable. "Why are you even here, Reg, shouldn't you be sleeping? Like a normal kid, bed and everything?"

"Normal," says Regulus. "Which part of this is normal? Maybe the part where I watched you turned into half a marble statue and beaten with a Holloway rod, and for what –"

"Telling lies," Sirius supplies helpfully.

"So what do you think you'll get for downright sabotage?" says Regulus. "Where did you put the pages?"

"I forgot," says Sirius, and he straightens up, thin body wrecked by silent laughter and lingering pain. "Isn't that just hilarious?"

Forgot.

That word shouldn't hit Regulus quite so hard – after all, he's forgotten plenty of things, most notably, an entire day on which he almost died – but it does hit him.

It hits him where it hurts.

Maybe it's the copy of Pensieves and the Magic of Memories he's just finished. Maybe it's the ghost's face that he saw with a new clarity today – a face he could have picked out of a crowd with confidence, but couldn't have said why -

Maybe it has been obvious to everyone but him.

"You think they're Obliviating us," he whispers.

It is out before he's had time to think about it, but it's the only thing that makes sense anymore. Too late, he remembers the spying portrait – but a glance at their visibly disgruntled great-grandfather shows him wearing giant, violently purple, painted-on earmuffs.

Those, he decides distractedly, are also a problem for tomorrow.

"Oh, Reggie," says his brother.

"You do, do you," Regulus says.

"You think they're Obliviating us," says Sirius. "You just want me to confirm."

It sounds ridiculous out loud, but then again: Welcome to Grimmauld Place, where the truth is quite strange and the past is made up.

Regulus holds on to the silence for a very long time, because he shouldn't – he can't –

"Say it, then," he says, because he needs to.

Whatever he's expected Sirius to say – he's disappointed. His brother has got caught up by a different piece of the conversation.

"Holloway rod," Sirius says thoughtfully. "So that's what it's called. Trust the Slytherin."

For the first time, he turns his head fully towards Regulus, bright eyes wide open, focusing on a point somewhere behind his head.

Two things fight for Regulus's attention.

"Are you Confunded?" is the first that comes out. "Oh god, your face," is the second.

Sirius sways like there's a breeze. "Yeah," he says, to one or the other question. Or both. "You're the pretty one now, Reg. It's a great responsibility."

"Tell me where you put the pages," says Regulus.

"I want them to see the ghost," says Sirius. "I want them to look in his adorable little face and tell him – tell him why they hate him so much – why they don't seem to like us any better, even though we are – we are still here."

He's rambling, a confused hand dragging through his hair, glowing cigarette end hanging limply from his bruised fingers, and Regulus knows, rather than cut his losses, Sirius is going to start the same fight tomorrow, and he's going to lose just as terribly, and they'll pull him out of Hogwarts to be home-schooled, and then Grimmauld Place will eat him.

"Sirius, look at yourself," he hisses, looking around the room for that hand mirror he's seen Sirius handling before. "You can't risk it. Just for once in your life, lie low and avoid trouble."

He finds the mirror lying face down on the desk, and Regulus springs up to grab it before Sirius can yelp and protest, sticks it in his face like an accusation.

There's a moment of terrible silence.

Then a third voice says, "Sirius, what the fuck? I've been trying to reach you all night!" It's as real as if he were standing here in the room with them.

"Maybe I don't want to talk to you," says Sirius. It comes out as a bit of a whine.

"Well, tough luck, princess, here I am."

Regulus looks around for the source of the disembodied voice before he realises it's coming from the mirror he's holding.

"Potter?" he says.

"Regulus?" says the mirror. "Oh, good. Suck it up, Sirius, this conversation is happening with or without you."

"Oh, piss off." Sirius settles back into the window frame, wincing as he does so.

Regulus is still staring at the mirror in his hands, where an angry and not entirely awake James Potter is staring back at him.

"Do you even know how many enchantments protect Grimmauld Place from this sort of thing?" Regulus asks.

"What? Oh, you mean this little mirror contraption," says Potter. "Yeah, pretty much. We're intimately familiar with every single one of them. What's wrong with Sirius?"

Regulus hesitates. But it's a bit late for their usual obfuscation tactics. "To be frank," he says, "there's a bit of a list."

"Is he hurt?" says Potter. "He looks hurt. Turn the light up and let me have a proper look at him."

Sirius is emphatically shaking his head, and Regulus has a lightbulb idea. Completely mad, he supposes, and unfortunately inevitable.

"I have something better," says Regulus. "Can you take him in for a few days? I'll send him through the Floo in a moment."

"What?" says Sirius. "No, he won't."

"Shut up, princess. Grown-ups are talking. Of course I can take him, Regulus." says Potter. However, he looks suspicious rather than overjoyed. "Why, though? What happened?"

"He did something dumb and I need to clean it up," says Regulus.

"Story of my life," mumbles Potter.

"It's possibly a tad dumber than what you're used to," says Regulus. "I need to do this before our parents find out."

It's another inch off the secret they've been so committed to keeping – but for what? The lesser evil? The lesser evil is what brought them here.

"Seriously, Regulus?" says Potter, in a voice of someone who's dealt with this bullshit before. "No. Don't do that. Come with him, I daresay we have room enough. It's only five days until the first, and things will calm down until Christmas, yeah?"

"Oh, Jamesie. Bless," says Sirius softly.

"Oh, for fuck's sake," says Potter. "Getting the pair of you to leave – honestly, it's like pulling teeth. It's like you like it there."

Regulus shakes his head, thinks of the tiny ghost and how it shouted down Mother. He thinks of bravery. "It's really not the sort of thing that sorts itself out," he says. "Kreacher will help me. I'll be fine."

Potter gives him a long, hard look, and Regulus is starting to realise why Sirius picked this boy as his brother-in-arms. "Fine?" he says. "Regulus Betelgeuse Black, you haven't been fine a day in your life. You're scared of water and you never learned to breathe correctly. And you still think Sirius caught the short end of the stick?"

Regulus fully expects his brother to protest, but nothing. Then he fully expects himself to protest, and apparently that's not happening, either. "Plenty of short ends around here," he mutters. "And it's Arcturus."

"No-one likes a martyr, Regulus, not even your parents," says Potter. "Come with him."

Incidentally, one thing one learns by hanging around in Grimmauld Place is how to detect a good provocation.

"Shut up, Potter," says Regulus. "Expect my idiot brother in ten minutes. He's Confunded, or something like it, so don't expect him to make too much sense for a while, and he's –"

"Hurt," says Potter, and his voice is low and angry. "I know."

Regulus swallows. This is not something that leaves the family, ever. Ordinarily, Sirius would spend the remainder of the holidays locked up in his room, and set out for Hogwarts under three layers of shoddy concealment charms. But Regulus can't see an alternative.

"Potter. The Black family has the country's high society and most of the Wizengamot behind them," he says. "Just so you're warned, it looks a bit…"

He takes in his brother's swollen face, his bruised jaw, whatever he's hiding under that blanket. "Well, it looks a bit bad…," he concedes. "Please, whatever you're thinking of doing – whatever your parents may think of doing – it'll backfire."

Potter nods, his lips a tight line. "Come with him," he says again, and closes off the call.

Regulus bullies his brother back into an upward position. He winces at the noises of pain Sirius makes when being manhandled, and tells him to shut up, then rummages in a drawer for the softest shirt he can find. He coaxes the blanket off his brother and acknowledges the chaos underneath just long enough to ask:

"Do you trust my healing spells?"

As Sirius vehemently shakes his head, Regulus says, "Good, me neither," and manoeuvres his brother into the shirt. No time to pack anything, but he summons Sirius's wand from across the room.

Sirius is not exactly cooperating, as such, but the Confundus does make him a little more suggestible, and Regulus has him downstairs in the living room with surprisingly little noise. Regulus thanks whatever god may listen that their parents have not yet thought of locking the Floo powder away, and quickly conjures the keyspell that unscrambles the magical fire and allows Sirius a safe passage out of Grimmauld Place.

Of course, Sirius chooses that very moment to regain his speech.

"Reg," he says. "Come with me, it's not safe here, it's not safe – look at me –"

"No, I can't," says Regulus. "Someone has to make sure they never see that ghost again, or they will kill you -"

Oh please, says a voice inside his head. Do you honestly think they could get away with murder?

But there's an eerie feeling, too, a sickly, weightless, ancient feeling, like one gets when one enters an abandoned building, or hops off the Knight Bus in the wrong neighbourhood. Like something is terribly, terribly wrong. Like he already knows the answer to that question.

"He's right, you know," says Sirius. "Father's right."

Regulus pauses his movements. "…Listen, I know you're Confunded, but –"

"He says I'm poisoning your mind," says Sirius. "So here goes. Poison for Reggie. I keep -" he draws a deep breath. "I keep forgetting, so I wrote it down."

He unfolds the piece of parchment he'd retrieved from the window, taps it with his wand until words break through the surface, like they're floating up from the deep sea.

Swaying dangerously, he says, "His name is Altair," he says. "And he was a squib."

Regulus feels his eyes narrow. "Squibs don't turn into ghosts," he says, and Sirius laughs.

"Who taught you that?" he says, and Regulus shoves him backwards into the green flames.

He hopes Potter is there to catch him on the other end.

Regulus steps back then. His mind certainly feels like it's been through the hoops, but somehow, things seem to come together, like he's caught on the edge of a dark and terrible secret, and he doesn't know the shape and the size of it, just that it all started in Blackpool, that long-lost day when he was five.

Pages, he thinks. Pages, Regulus. Focus. If they find out that the ghost is still here, it'll all be over.

"Altair," he whispers under his breath, trying out the name in the emptiness of the living room. It echoes.

"Altair, Altair," he says. "Little ghost, you have to leave. You can't ever come back. I'm sorry you're dead, but they'll kill Sirius, too."

The living room is spacious, full of cabinets, the cabinets full of books and dark artefacts and things that will bite him, it's just one room and yet a million places to hide a piece of parchment, and momentarily he falters at the sheer size of the task he's set himself: To clean up after his idiot brother.

And then he remembers his brother's face when he said, "Twelve", and he tries to remember how much time Sirius has spent in Father's office over the years, and he can't. Payback time, then.

His mother saves him the trouble. He hasn't even started, still rooted to the floor in the middle of the living room, when he hears the door open behind him.

"And what do you think you're doing at this time of night?" she says –

- and he wants to be cunning, and he wants to be clever, and he wants to be faithful, and he even wants to be brave. All four require that he not give this away. That he keep this one secret, tell this one single lie. But he needs to know.

"Who was Altair?" he asks.

And after the long, terrible silence has passed, she says, "Turn around, Regulus. Look at me."

And he does.

To be continued.