Disclaimer: This is a work of fanfiction based on the Harry Potter universe. All recognizable characters, plots, and settings are the exclusive property of J.K Rowling. I make no claim to ownership.

Acknowledgements: Thank you to my editor Athena Hope as well as my betas 3CP, Fezzik, Luq707, Raven0900, Regress, and Yoshi89 for their work on this story.

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September 4, 1942
The Dungeons
10:30 PM

Harry had never moved so stiffly as when he stepped out of the Slytherin common room that night. Every muscle in his body was as tightly wound as a coiled spring, ready to lunge, dive, or flee at any moment. He could have sworn that the temperature dropped by five degrees the second he stepped into the corridor beyond the common room, but he knew he was imagining the whole thing.

“Good evening.”

She spoke quietly, but her voice seemed to ring through Harry’s head as if she had shouted at the top of her lungs from the peak of a towering mountain. It cut through the silence of the night like a poisoned dagger. The way Harry’s heart seemed to miss a beat, one might think it had been he who the metaphorical blade had pierced.

“Evening,” he responded mechanically.

She wore her standard Hogwarts robes with the prefect’s badge pinned to her chest. Her long black locks cascaded straight down her back. Not a single hair was out of place, nor was there a blemish anywhere on her pale skin that Harry could see. A small twinge of annoyance pricked at the corner of his mind, but he shoved it aside. It would not do to be upset by something as inconsequential as the fact that Riddle took care of herself.

“How was your first week at Hogwarts?” Riddle asked, gesturing for Harry to follow. She turned and began towards the stone steps that would lead them up to the castle’s main floor without a backwards glance.

Harry wondered whether she was that used to people following her without a second thought. It was a disturbing possibility, but one he didn’t stop to consider in depth. He hastened to follow her. His shoes echoed against the ancient stones as he moved, but his companion seemed to glide instead of walk. Her steps were so soundless that Harry wondered whether or not she had placed some kind of enchantment on her shoes.

“Decent,” answered Harry. “Some classes are easier than others, but they’re interesting.” He grimaced. “Except for History of Magic.” Harry had hoped that Binns might still be alive at this point, but apparently, he was not. Why he had thought that would make the professor any more interesting, Harry wasn’t sure.

“Binns is an awful teacher, yes. A shame, really. History is such an important subject, yet no one takes it seriously because of the droning fool who teaches it. There’s so much we can learn from history.”

Her words sent a strange chill running up Harry’s spine, but he said nothing. He thought back to Tom Riddle in the Chamber of Secrets preaching about his own family history. The boy must have been well-versed in more of the past than that if he had found the fabled Chamber of Secrets.

Thoughts of the two Riddles swam to the surface of his mind once more. Their faces seemed to hover beside one another, rotating to rest at different angles for Harry to examine them. He wished he could do more. He wished he had known more about Tom Riddle. It might have helped him compare the boy to his female counterpart in this alternate reality and try to glean the truth. Perhaps it was that he was much too on edge for this meeting, or perhaps he should have taken any available excuse to have not shown up at all. Without much more information, he would never be sure.

“I’m glad you’ve enjoyed the classes so far, nevertheless,” Riddle continued. “How did you fare in Arithmancy and Ancient Runes?”

Harry fought back a scowl as he remembered the test he had taken and horribly failed in Ancient Runes. The answer was not well at all, but he hoped the truth of it was not written too plainly upon his face.

“They were… difficult, but I think I’ll manage to figure them out. Arithmancy isn’t bad, just a bit head-spinning. Runes was rough, but I’m sure I can work through it.”

“Remember what I told you, the offer of help is always open.”

He hated how she spoke in a way that sounded so genuine. It just made Harry want to trust her, but he knew doing so would be foolish. He couldn’t accept help from Riddle, but every syllable she spoke seemed to draw him in. It was a sort of magnetism he had never experienced and it made him shiver. Or perhaps that was the long, dark shadows that seemed to slither across the floor and leap from wall to wall as the torches flickered and cast them about the corridors. They looked like stalking predators out of the corner of Harry’s eye and they were the last things he wanted to see whilst alone with Riddle.

“I’m glad you’re confident,” she said. “How much of the castle have you gotten to explore so far?”

He shrugged. “Quite a bit of it. It’s what I’ve been spending a lot of my free time doing.” What he had actually been putting most of his time into was duelling and practicing with Elena, but Riddle didn’t need to know that.

“Which floors have you least explored?”

“The higher the floor, the less time I’ve spent on it.”

They climbed the marble staircase until they stepped onto the third floor. They mostly walked in silence as Riddle periodically flicked her wand. Every time she did, Harry felt… something caress him. He thought it was some kind of magic, but he somehow suspected it had little to do with him. He had no idea what spell she was casting, but after a time, he grew curious enough to ask.

Riddle’s lips curved upwards when he did. “The Homenum Revelio Charm. It’s a variation of the Revelio Charm that only detects human presences.”

He frowned. “So when you cast it and I feel…”

“It’s the magic and the way the spell works.” There was a light behind Riddle’s eyes that Harry had not yet seen. It didn’t look like one of malice, or cruelty, or even cunning to Harry. It just looked… passionate? It looked as though they had touched on something that had caught her attention in a way he had not seen it grabbed before. “The spell emanates out from the caster. It spreads out in circular waves.

“So when the spell touches you, it tells the caster that you’re there?”

Riddle twirled her wand through long, pale fingers as her other hand idly twirled a lock of raven hair. “Yes and no. It doesn’t touch the person — the spell goes deeper than that.”

“Deeper… how?”

“I’m… not entirely sure. It’s an extremely complicated spell. Its arithmetic equation is unlike almost any I’ve seen.” That seemed strangely significant, but Harry could not imagine how.

“How do you cast it?” Something hot and foul was boiling in the pit of his stomach. It threatened to rise up and scorch the walls of his throat, but he fought it down. Not until he uttered the words did he realize it was frustration and disappointment; not in Riddle, but in himself. He should not be conversing with her the way he was.

She eyed him carefully. “How good are you with Charms?”

“It’s one of my better subjects.” It really was now that he had spent a great deal of the summer working on it. “I’m better at Defence Against the Dark Arts, but my Charms work has always been solid.”

“It’s a NEWT-level spell, so you may have some difficulties, but I’ve never found it to be terribly difficult.” She spun her wand in a swift, sharp circle before jabbing it outwards. The motion was deft and precise; the movements were tight and there was no wasted motion. “The incantation is Homenum Revelio and you must focus. Visualize like you would when transfiguring something.”

“What am I visualizing?”

“Where you want the spell to travel. Picture it like a wave flowing out in all directions — it should move straight through walls, floors, and ceilings.”

Harry withdrew his wand and focused on what she said. He played the image of a wave emanating outwards just as she had said and copied the wand movement the best he could.

“Homenum Revelio.”

Riddle herself had cast without words, but Harry knew that type of magic was beyond him for now. He didn’t expect the spell to work at all on his first try, but he nearly jumped out of his skin when he felt it. It was like a flash of white at the corner of his eye and the overwhelming feeling of knowing exactly where someone was. That someone was Riddle, clearly, and he felt nothing else. The spell had worked! Though something felt… incomplete?

Riddle’s eyebrow rose. “A very good first attempt. You felt the spell detect me.” It was more a statement than a question, but Harry nodded anyway. Riddle twirled a lock of hair again. “Impressive, Pavonis. A few of my friends have been struggling with that charm. It wasn’t perfect — the spell died after only spreading a few feet from your wand — but it was a very impressive first attempt.”

Harry felt his lips curving up into a smile and bit down hard on his tongue. The metallic taste of blood filled his mouth, but he regretted nothing. He shouldn’t be doing this! He shouldn’t be asking her for advice, let alone taking it. Smiling at her praise… no. It felt wrong… poisoned, like something about it was tainting his very soul.

Yet his lips wanted to curve upwards and he hated it. He had learned a new spell. That part at least was nice. Yes, better to focus on the learning than the teacher. That was much easier and it made him feel much less guilty as his footsteps continued to echo through the silent halls of Hogwarts castle.

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September 6, 1942
An Abandoned Classroom
9:37 PM

The clatter of Harry’s wand hitting the floor was almost deafening. It seemed to cut through the air like the snapping of a branch in a pitch-black forest late on a noiseless night.

Harry fumed as he walked over towards it, shaking his head slowly as though to clear it. That was what he really needed to do. His thoughts had been a jumbled mess of questions and emotions ever since he had toured the castle that Friday night with Riddle.

He still despised himself for how he had felt about the whole thing. He should have hated every minute of it. Until there was definitive proof that Riddle was not the same monster he had known in his own world, he should be treating her as though she was already Voldemort. Yet he had spoken with her, answered her questions, taken her advice, and almost even smiled at her… and it got worse. He had even spent time practicing the damn spell that next day.

Harry had tried to focus during the duel with Elena, but she had cast a spell he had never seen before. It caused a thick veil of smoke to rise and cloud the very air around the room. Harry found himself unable to see three feet in front of him as he choked and gasped for breath. The thought of the Homenum Revelio Charm had crossed his mind then and he had raised his wand. Then his brain had caught up. It was so wrong. If he used the spell Riddle had taught him to beat Elena… but he had to beat Elena. If he couldn’t beat Elena, what good would he be if Riddle ever became the monster he had once known?

It had been the pause that cost him. A bolt of crimson light had appeared from out of the smoke barely three feet away from Harry and he had been unable to dodge in time. The spell had ripped his wand from his hand and sent it spinning through the air and bouncing across the classroom’s floor. His concentration had lapsed and his thoughts had cost him — thoughts that still lurked, impatient and unresolved.

Damnit!

“Are you all right, Harry?”

“Fine,” he answered shortly, scowling as he snatched up his wand and whirled to face her.

Elena blanched and Harry frowned. He wondered if he had really looked that bothered. “Sorry,” he said, “I didn’t mean to come off as snappish. I’m just… annoyed.”

“You should be,” said Elena. “Any time I’ve beaten you lately, it was after a long and drawn-out duel when I used something you didn’t expect.” She scrunched up her face as though she smelled something unpleasant. “And those times haven’t been often.” She watched him closely. “Are you sure you’re okay?”

What on Earth could he tell her? That learning magic from a girl who might grow up to murder his future parents was bothering him? That he felt as though he was consorting with the darkest magician to ever grace the British Isles? That his mind had been plagued with the words the Riddle of his time had spoken whilst down in the Chamber of Secrets.

“There are strange likenesses between us, after all. Even you must have noticed. Both half bloods, orphans, raised by Muggles. Probably the only two Parselmouths to come to Hogwarts since the great Slytherin himself. We even look something alike…”

“I’m fine. Really. Just… distracted.”

It was a kind word for it, but there was nothing else he could say. He felt trapped.

He remembered all the times he had wanted to tell one of the teachers at his old primary school about how horrible Dudley was, but he knew it would be to no avail. That was what this felt like, but the stakes were so much higher. This wasn’t about bullying and abuse. This was about destruction and murder.

Well… maybe.

His hand twitched and he had to fight the urge to slam it into his own forehead. A sharp stab of pain manifested behind his eyes. It felt almost as though his scar was burning, but it had not so much as twinged since he had landed in the past.

“Let’s go again.” Harry raised his wand and took aim at Elena.

The youngest member of House Fawley looked hesitant, though she stepped gracefully into her stance after a moment’s pause and allowed a look of determination to rest upon her features.

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September 7, 1942
The Defence Against the Dark Arts Classroom
9:10 AM

The air was thick with tension in the Defence Against the Dark Arts classroom the Monday after the students had arrived at Hogwarts. Their first lesson in the class had been an interesting one to say the very least. It featured a boggart, a pseudo-dementor, and the Patronus Charm. It had been by far the most eventful lesson Harry had experienced since arriving back in the past and he could only wonder how this one would compare.

“Pavonis,” barked Merrythought, “to the front of the class with Fawley!” She pointed sharply to the front row of desks. Harry scowled but hid it behind his hand, feigning a yawn. He disliked people sitting behind him.

“She likes you,” Elena whispered as they moved towards their designated places.

“She’s got a funny way of showing it,” Harry muttered back.

Elena rolled her eyes. “It’s Merrythought. She doesn’t really do affection. You just learn to look for certain things.” She shot him a conspiratorial glance. “She always puts her favourites in the front. I think it’s so they can get a better view and the like.” Now it was Elena’s face that scrunched up in distaste. “And so she can pester you with questions… I do wish she wouldn’t do that.”

Harry sat at the furthest desk to the left in the front row, with Elena to his right and Dorea Black to hers. Merrythought waited for all students to be seated before standing from behind her desk. She did not immediately speak. She paced before them like a rabid lion stalking its prey. It only added to the mounting sensations of anticipation and tension.

“Fourth year at Hogwarts is when students in this class start learning about curses and the like. You really ought to be taught them sooner, but I don’t write the curriculum. What I do approve of is that, this year, they’ve made a major change to the way we do things.

“The ministry is finally waking up and realizing that we have a war on our hands. It’s because of the war that the curriculum in this class is changing. They’ve finally decided not to baby you all the way through to N.E.W.Ts. They’ve decided to let me show all of you what the worst of the worst really is.”

She flicked her wand and a drawer opened on her desk. A box floated out of it. Harry could hear shuffling and squeaking from within the box and wondered why until it was opened. Several mice tried to escape right away, but Merrythought cast some sort of spell around the box and they seemed unable to move past the container’s edge.

“Curses come in many shapes and forms. Some curses don’t do all that much damage. The Full Body-Bind is technically a curse. Who can tell me what that curse does?”

She pointed to a dark-haired Slytherin near the front of the class who Harry remembered was called Avery. “It paralyzes the target. Their arms and legs become pinned to their body and they’re unable to move a muscle.”

“Correct — take three points for Slytherin. Anyhow, there are curses like the Full Body-Bind that only cause temporary paralysis, but there are things much worse. There are curses that can burn you from the inside out, curses that make breathing impossible, curses that shatter bone, and curses that obliterate organs.”

Her expression was suddenly very hard and Harry could not help but wonder whether or not he had ever heard a class so quiet. Their complete and undivided attention was fixated upon Merrythought, who watched them all with a stern yet pensive expression.

“And yet,” she continued, “none of these are the curses that the Ministry of Magic deems as the worst of the worst. There are several curses that they categorize as being… unforgivable.”

Harry could hear robes rustle as students shifted nervously in their seats. He cast his eyes about the room and saw that many gathered were stone-faced. Elena was among them, as was Dorea. Avery was less stoic. Every muscle in his face seemed as though it had been pulled tight, like an elastic band stretched to its breaking point. Harry thought he looked as though he was trying his best to suppress some sort of expression. What exactly that was, he was unsure.

Merrythought had pulled a mouse from the box during the time Harry had looked away and set it on the desk. The thing was squeaking and scampering like mad, but Merrythought kept blocking its retreat.

“There are three curses that the Ministry of Magic holds more evil than any other spells. They are called the Unforgivable Curses because the use of any of them on a fellow human being would immediately earn the caster a life sentence in Azkaban.”

Harry shuddered at the mere mention of the prison. He could practically hear the dementor’s deep, rasping breath and feel the oppressive cold settle over him like an invisible blanket of ice.

“Luckily,” the professor continued, “the ministry doesn’t say anything about casting them on animals, so I can show you exactly what it is you might deal with if terrorists decide to attack Britain again.”

She took a step back and raised her wand before taking aim at the mouse. It was still scampering this way and that, but Merrythought didn’t move her wand. She just waited for it to run into the line of fire, at which point she barked out her incantation in a sharp, whip of a voice.

“Crucio!”

There was no burst of magic following the incantation — no flash of light, puff of smoke, or any sort of loud and dramatic bang.

The fact only made it all the more disturbing when the creature collapsed midstep, rolled over onto its back, and began letting out a horrible, wheezing stream of squeaks. They were so high and sudden that it sounded like a sonic boom. Except for the fact that it didn’t end. The cacophony rose and stretched on as it mounted until the sound seemed to pierce not just Harry’s ears, but his very skin and bones. The mouse’s legs were twitching now as if arcs of electricity raced through the creature’s veins like fast-flowing blood.

It was over as fast as it had begun. The creature collapsed in on itself as soon as Merrythought lifted her wand. Its little chest heaved, but all of its other muscles seemed to have given up some time ago. It still breathed, but it dangled limply as Merrythought tossed it back into the box and withdrew one of its companions. She held it aloft above the desk as she turned to the class. Harry wasn’t sure whether to be impressed or disturbed at how unphased the woman seemed by the whole thing.

“That was the Cruciatus Curse,” she explained. “For those of you duller than an ancient quill, it’s the most potent torture curse that exists. It over stimulates every nerve and causes pain the likes of which you could never imagine. Muscles have been known to tear due to the stress, people’s minds have been lost, and their hearts have stopped. There are even some cases of victims tearing out their own eyes or throats.”

Many of the faces dotted around the room were as grey as the rain-flecked sky outside. They still all watched Merrythought, though a few did so with what seemed to be reluctance. Elena seemed as though she might be sick. Harry felt a touch queasy himself, but nothing more. He had seen his best friend and godfather have their souls sucked out by rotting creatures who feasted on happiness itself. Hearing a mouse squeak was nothing compared to that.

“Some say the Cruciatus Curse is the kindest of the three,” said Merrythought, setting the second mouse down upon the desk and turning her wand towards it. “I’ll let you all be the judge of that.”

Harry wondered what would come next. Was one of these spells something like the dementor’s kiss? Was there something worse? Or was the rising suspicion in the pit of his gut about to be proven right? Merlin… he hoped not.

“Imperio!”

Watching the first mouse do its best impression of a human’s agonized scream had been gut-wrenching in its own way, but seeing the second follow each and every command Merrythought uttered without a single thought was every bit as terrifying. What disturbed Harry the most was that some of the commands she gave the creature should have been well outside of its capabilities. Yet, the mouse complied — and succeeded.

Harry’s gut twisted when he realized that he was intrigued by the fact. He wondered what the spell’s limits were. Would a witch or wizard placed under its power be able to perform magic they had never seen before? Would they be able to leap higher than any man before them? Would they be able to run faster than humans had thought possible? There were so many possibilities, yet Harry knew he should be considering none of them.

He wasn’t sure how disturbed he may have been had the thought been allowed to linger, but the professor was already withdrawing the third mouse from the box with a grim expression.

“That was the Imperius Curse. I’m sure I don’t need to tell any of you what it does. I should point out that the curse can be fought, but only by one with extraordinary will or certain training that I doubt many in this room will ever undertake. Training that I will not provide. The ministry wants you to know what you’re fighting, but the curses when cast upon another human are unforgivable for a reason.” Her eyes darkened. “Which brings us to the final curse of the set.”

She set the mouse down upon the desk and raised her wand with a flourish. Harry’s heart was beating faster now. It was as though the muscle knew what was coming next, even as his mind contemplated whether or not this would be what he was dreading so deeply…

“Avada Kedavra!”

It was as he remembered. The room was alight with pale green light brighter and more vivid than any emerald. There was a sound, too. It was akin to the sound a whip might make whilst sailing through the air, but a hundred times worse. It seemed to resonate within Harry and echo off the very walls of his chest. It was a rushing sound that whistled with the promise of what would come next, though there was no impact.

Just that blinding flash of light and then nothing at all. When the vibrant spell faded, the third and final mouse was lying motionless upon the desk. Harry remembered the way its counterpart’s chest had heaved after being tortured, but there was nothing of the sort this time around. It had fallen like a puppet with its strings cut and Harry knew it would never rise again.

He pressed his eyes tightly shut as unbidden memories surged forth. Memories of long and miserable nights in his cupboard. The way Aunt Petunia’s hurried knocking would not just wake him, but pull him suddenly from that halo of green light. Sometimes when he awoke, it would still be stained upon the inside of his eyelids, or so it would seem.

Yet the dreams paled in comparison to the thing itself. He had seen it last year — well… fifty-and-a-bit years from now — whenever a dementor had drawn too near. The way that sickly light had filled the room as his mother stood before him, arms outstretched as though crucified before the light took her and snuffed her life out as swiftly and easily as an extinguished candle.

“Harry?” It was Elena who had spoken. Her voice was a whisper right beside his ear, though it might as well have come from a hundred miles away. Harry didn’t react. He heard it vaguely, but he just let it wash over him like fast-falling water droplets. His eyes were fixed unblinkingly on the front of the room. His expression was unmoving and unchanging.

He felt nothing. It was strange to know he should feel sick, or hurt, or angry, or even depressed. It scared him to know that emotions should be crashing against his walls like a hundred battering rams, yet they simply failed to reach him. They were more like arrows fired from afar against a strong and vengeful wind. They might have rushed forth with malicious intent, but they would never reach their target. They would never pierce Harry’s wall of numb shock and force him to feel.

“The Killing Curse,” Merrythought said softly. “Some say it’s the worst of the three while others say it is a mercy. What makes the curse so powerful is that it never fails. No one has ever been hit by that spell and lived to tell the tale.” Her expression was as blank as Harry’s. “And just like the other two, there is no known form of magic that can block or shield someone from it.”

Only the lives of the people who could have made Harry’s childhood worth living, he thought. That was the price to survive the unblockable Avada Kedavra curse. It was a price he had paid in full. He would never know what his life may have been like had the debt not been levied upon him, all he knew was that it was a price much too high to ask of anyone. All he knew was that no matter how long it took or how treacherous the path might be, he was going to do his best to ensure that no man, woman, or child had to pay that price.

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Author’s Endnote:

This is a short chapter compared to the others, but I don’t anticipate most CoP chapters being very long. It’s just that the setup ones sort of just had a lot of necessary content.

I know the last scene was very similar in its contents to the one from GoF, but I hope you all understand why it needed to be there. It affected Harry in a very different way from a psychological perspective and I think that process was important to show.

Regardless, do let me know what you all think as always.

Please read and review.

Thank you to The Darkling for his corrections/contributions on this chapter.

A massive thank you is also extended to my Olympian-level patron, ShadowWolf, for his incredibly generous support on that platform!

PS: The next chapter will be posted in exactly two weeks. It will release for readers on FFN and AO3 on Wednesday, September 29th, 2021. It is available RIGHT NOW to anyone who joins my Discord server. Those who sign up to my Patreon page will gain immediate access to the next FOUR CHAPTERS.

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