AN: "An Occlument Heart" follows canon (more or less) up to the beginning of Book 5, when the story begins.

One: To Revise What Has Been False

It could have been another story, the one that was meant

Instead of the one that happened.

—Mark Strand

At 12 Grimmauld Place there was a clock in every room.

The grandfather clock in the ground floor hallway, of course, a cranky bastard that spat out bolts whenever Sirius passed. The pretentious tock of its pendulum could be heard all the way to the second floor of the old drafty house, along with the intermittent thud of a bolt hitting the floorboards when the clock fired at Kreacher or a rat scuttled by.

There was the rusty clock embedded in the kitchen wall, which grated every time the spindly iron minute hand shifted with a tick-scriiiitch. The mantle clock in the dining room that would drive anyone mad with its hyperactive tick-tick-tick-tick-tick. The subtle self-winding pocket watch Sirius was sure he would find if he could ever open the bathroom drawer some long-deceased Black had magicked shut. The alarm clock in Sirius's bedroom that kept a measured, quiet, normal tick-tock, tick-tock all day, but at night kept him awake with its incessant sound, seeming so much louder in the dark, silent room.

In the guest rooms; in the pantry; in his brother's and his parents' rooms. Sirius knew them all.

At this moment, he was listening to the once-a-minute tick-scriiiitch of the kitchen clock, while he swore and waved his wand in the general direction of a broken radio that was lying uselessly on the table. He picked up the radio, pointed his wand at the antenna, and it wilted like a cooked noodle. Sirius swore again, more loudly, and threw the radio down the table so hard that it knocked over a stack of newspapers, which collided with a jar of glass eyes, which skidded off the table and smashed on the floor. Glass eyes rolled haphazardly all over the place.

"Bollocks," muttered Sirius. The clock scritched again as he knelt down, using a mending charm to gather the eyes—Kreacher's, presumably, God knew what for—and reassemble the jar.

He had just returned the eye jar to the heavy wooden table when something made him pause, with his head cocked, listening. It was the click of a doorknob.

It was upstairs. Someone was coming in! Sirius grinned involuntarily and rushed toward the stairs, knocking the eye jar to the floor again. But he stopped at the door to the stairs, reminding himself to be careful—it could be anyone; plenty of people were looking for him. He leaned against the door, listening, as the eyes scattered over the tile.

"Sirius!" The commanding voice upstairs was Dumbledore's! Sirius grinned again, pulled the door open with a theatrical flourish, and dashed up the stairs. On the way up, he put on a serious expression to match whatever business Dumbledore undoubtedly had. No one came to 12 Grimmauld Place for tea and cookies.

But when Sirius reached the top of the stairs, his excitement plummeted into revulsion. It never ceased to disgust him, what the Death Eaters would do to another human being.

Dumbledore had his wand out and was magically supporting a limp form whose dark hair, matted with blood, had fallen into his face. Gashes in his grimy black robes revealed deep cuts crossing his body. But Sirius knew that the worst tortures left no physical mark; the figure lifted his head and Sirius saw Severus Snape's eyes, filled with the mad emptiness that comes from too much time in a place without hope.

"Azkaban?" he asked without thinking.

"No. He has been acting as a spy for our cause for several years—that is, until Voldemort discovered his real allegiance," Dumbledore explained shortly, following his usual pattern of telling Sirius only the most basic information, only when it was absolutely necessary.

Sirius would have said something about it, but Dumbledore was already walking purposefully up the stairs, Snape floating before them. "What room is best?"

Sirius kept two first-floor rooms clean and ready for visitors. He gestured toward the larger one.

"It took us some time to get him out of there," Dumbledore continued as he transported Snape into the room, lifting the comforter aside with a wave of his hand and gently lowering the man, who winced when his back touched the sheet. "He knows things that we could not allow Voldemort to know."

"Told them nothing," Snape murmured angrily. "Your precious Harry, precious plans."

"Thank you, Severus," Dumbledore said gravely, then spoke to Sirius more softly. "I do not think his life is in great danger from these wounds, but something to speed his healing would not be amiss. He'll need to stay in bed for several days, I expect. And of course, even given his skill in Occlumency, we cannot risk …" He trailed off, glancing toward Snape writhing and muttering against the sheets, then turned back to Sirius. "It is imperative to the success of the Order that he not leave this house."

Dumbledore paused for a moment to brush the hair from Snape's face, looking very old. Then he straightened and said, to himself more than to Sirius, "I must go; there are many more things that need doing tonight. I'll leave you to it." And he left the room in a whirl of robes.

Sirius listened to Dumbledore's decided footsteps recede down the staircase. The front door clicked, and he was alone with Snape. Sirius was not the type to enjoy having a man he detested at his mercy like this, and was instead bewildered to see how strongly he could feel pity for someone he had never pitied before. He thought of himself and James at Hogwarts, and tried not to feel ashamed. He had been different then.

"No less than I deserve," Snape murmured deliriously. "Fifteen points for Gryffindor."

Sirius went to retrieve materials from the bathroom cupboard, and when he came back Snape was quietly reciting Livius's Meditations of the Occlumens. "Nothing is good or bad without first being determined so by the mind. Pain cannot touch the mind. Fear is subservient to the mind. No wall can imprison the mind…."

Sirius vanished the other man's robes, painfully aware that he was the last person Snape would wish to invade his privacy this way.

"The body is the vessel and the anchor of the mind," Snape intoned. "The mind is both one and multiple…."

Sirius wet a cloth with essence of dittany and applied it to the first wound. "No," Snape said when the dittany stung his collarbone, his eyes opening wide in terror, but upon seeing Sirius he closed them and relaxed.

"The mind has many rooms," Snape repeated to himself as Sirius continued his task, "Memories half-forgotten and secrets long locked away. In these natural protective barriers lies the power of the Occlumens. The Occlumens must divide himself from his weaknesses. The Occlumens must divide himself from unfulfilled desires…."

Sirius gently guided Snape onto his front, and the patient obeyed passively. "The Occlumens must not permit a thought that could become a weapon to his enemy," he said. "The Occlumens must place his trust in the strength of his mind…." Sirius concentrated on each wound one at a time.

At last Sirius had bandaged the last long gash and helped Snape turn over. "With luck they won't scar," he said, not certain whether Snape would hear or care in this state. "A scarred mind is a protected mind," said Snape before Sirius poured a sleeping draught down his throat.

March 1976

"What's this Snivellus's got?" James's shadow fell across the bench where Snape was sitting.

It was Sunday afternoon, and Snape should have been studying for the OWLs—usually would have been, in fact; he would never know how James had guessed that he wasn't. But James had that preternatural ability to be an ass at the most inopportune times, and he snatched Snape's notebook away.

"No!" Snape pleaded, and instantly knew it was a mistake to let James see that it was getting to him. Stupid. He glanced nervously around the quad.

"Merlin's pants, it's a poem!" James exclaimed, as though he couldn't believe his luck. A crowd was starting to form—mostly Gryffindors, but a few Ravenclaws, too.

"Unbelievable! What are you waiting for? Give us an oration, mate," Sirius said from the sidelines. Sirius was here, too, then, Snape thought, and supposed it didn't actually matter.

James nodded. "Ahem." He stood up straight and adopted a professorial tone. Snape began to feel nauseous. And James began:

Your dazzling smile, like sunlight, breaks the dark

Where in the shadows watching you I hide.

"Could it be?" James addressed the crowd with mock delight. "Is Snivellus in love?" They all laughed, and Snape wished he could disapparate. James went on in mock sorrow, with dramatic, vaudevillian gestures:

My suff'ring soul forever bears your mark

And everywhere I look I see your eyes—

"Christ, Snape, it's bloody atrocious!" Sirius interjected.

"Yeah," Peter added inanely. He was clearly nervous talking in front of so many people. "What kind of qu-queer writes poetry anyway?" He stuttered over the name that Snape liked even less than the others he was called.

"Now, now, Peter, be nice"—Sirius held out a hand to silence the laughing crowd—"or else Snape won't let us hear the rest." As if Snape could possibly refuse. "Don't you want to hear what happens next to Snivellus's suff'ring soul?" The cluster of students chuckled and quieted, and Snape wished he could have that kind of power over people.

James went on:

You hate me still, but yet you turn to him,

One who deserves you even less than I.

He's smug, a daft and heartless, mindless jock—

A Gryffindor, the type epitomized.

You waste yourself in his admiring crew,

And I, likewise, will waste myself on you.

James's delivery grew more and more melodramatic as the poem carried on, and by the final line he fell into a theatrical swoon. Peter and Sirius caught him; like everyone but Snape, they were laughing. Snape concentrated on clearing his mind to keep himself from blushing. It was the latest useful application he'd discovered for Occlumency—and he hated it when they could see he was ashamed.

"So, suff'ring soul," James addressed Snape, "who's it about? What lucky chick is on the receiving end of your eternal passion?"

"Eternal stalking, more like," Peter suggested hesitantly.

James gave Peter a little encouraging nod. "Yeah, who are you watching from the shadows, Snivellus?"

Snape had learned by now that it was better to say nothing. The giggling crowd began to disperse.

"I bet we can figure it out," Sirius said, and everyone turned back toward him. Snape willed his mind blank again, forced his shoulders to relax. Sirius carried on, "I mean, the cocky Gryffindor bastard has got to be you, James. Mindless jock? Smug and daft? Snape's got you pegged, I'd say."

Sirius was grinning, but James's expression darkened as he drew his own conclusions. He turned toward Snape with hard eyes, shoving the paper in his face. "Is this about Lily, you greasy little worm? Is it?"

Snape said nothing, and let nothing show in his face.

"Answer me, Snape." James's tone of voice suggested a kind of violence that Snape had not yet experienced at school. Silence wouldn't work this time.

"Yes," he said, "it's Lily," and when James punched him he was relieved.