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, Thanos, and Yoshi89 for their work on this story.

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March 13, 1943
The Chamber of Secrets
9:56 PM

It had been two weeks since the attack on Myrtle Warren, and the castle was still in disarray. The whispers had been constant, the school abuzz like a thousand raging bees. The students spent the rest of that first day locked down and, for the next week, a teacher had been assigned to stand at the door of the Great Hall during all meals and gatherings. The patrols had been almost doubled through the halls, something that Harry loathed. It made slipping out of the common room or sneaking around at night much more difficult. Not for the first time, he wished more than anything he had possessed the foresight to carry his invisibility cloak when the time turner threw him back into the past.

All the students had waited eagerly for the diagnosis on Myrtle, Harry most of all. Dumbledore had been confused at the scene of the crime just like he had been during Harry’s second year. It had been a bad omen.

Myrtle was alive, but completely unresponsive. The rumours said she was paralyzed or — to use a different term Harry had heard thrown around — petrified.

Most of the student body had been speculating as to what kind of magic was even capable of such a thing, at least when they weren’t busy trying to piece together exactly who the culprit was. Even Riddle and her group of friends were not untouched by such speculation.

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Thirteen days ago…

Harry sensed unrest in Riddle from the moment Myrtle’s body was found. What did it mean? Surely she was the Heir of Slytherin. That was the only thing that made sense, but… did it? How had she gained access to the Chamber of Secrets? Surely this was much too coincidental to be the work of anything other than Cerastes, but that too had its problems.

Cerastes did not strike Harry as a good actor. Snakes had little use for such talents, and the basilisk had always been blunt.

It just didn’t make sense. Harry had resolved to watch Riddle even more closely in the coming days and weeks, but he feared it would be for naught. Emily Riddle had an astounding talent for making things even more confusing and Harry somehow suspected that would be the case yet again, though he could not imagine how things could grow more complex than they already were.

He had been able to glean little of her mood beyond the restlessness. She made no attempt to hide it, instead pacing often in the common room, which they had been confined to whilst the teachers searched the school.

That search took the rest of the day and bled into the next, but at long last, the lockdown was lifted. Riddle looked more pleased to leave than anyone. Harry could not blame her. If she was the attacker, she had likely been wracked with nerves, worried that someone on the staff would discover a piece of evidence. Even if she hadn’t, the whole of Slytherin House was sure she was the culprit. The whispers were practically deafening all throughout the common room and though Riddle had paid them no visible heed, Harry knew she heard them.

Classes went as per usual that first day out of the common room, but the tension was unlike anything Harry had ever seen. In his own time, students had at least been somewhat accustomed to oddities at Hogwarts; what with the Defence Against the Dark Arts Professor changing every year, a troll in the dungeons, and a cursed bludger all being fresh in everyone’s memories. This student body was not nearly as conditioned to expect things out of the ordinary and they were all on edge with the war heating up on the continent and Grindelwald’s forces having been especially vicious since their defeat at Stalingrad.

Harry marvelled at Riddle’s control all throughout dinner. Everyone in the group knew that a meeting would soon come, yet she showed no indication. There was no haste in her movements, no tension in her muscles, no lack of grace in her posture or manners. Harry had never met anyone her age with such composure. This was what a Slytherin was supposed to be. The snakes of his time were pathetic compared to this. Someone like Draco Malfoy could never have made this act work.

Now that Harry thought about it, it wasn’t just Riddle. The collective IQ of Slytherin House seemed higher in these times. It made some sense. Many of these childrens’ parents had lived through the Great War and now, their children were living through another. That had to breed a certain kind of person, especially when that was mixed with the harsher traditions and more strictly-enforced etiquette of this age.

Despite her composure, Riddle practically demanded all of them finish quickly once she had. She said nothing, but her stares made her wishes clear. When they had all pushed their plates away, she led them from the hall and Harry quickly realized one of the few good things about Riddle revealing herself as a Parselmouth — there were an astonishing number of secret passages that were triggered by speaking Salazar’s sacred tongue.

Harry frowned as they moved through a dark, winding passage sloping steadily upwards. He remembered none of these being on the Marauder’s Map. It made some sense — the Marauders had never discovered the Chamber of Secrets and none of them were Parselmouths — but it still worried him.

Along with the chamber and the Room of Requirement, this was now the third time Riddle had shown off knowledge of the castle greater than even the Marauders. It was just one more advantage she held over Harry and, in that moment, he realized becoming magically powerful might not be enough. He resolved to make more night time excursions around the castle and discover more for himself. Now that she may really be the Heir of Slytherin despite his intervention, Harry feared he would need every available advantage.

They reached the secret room on the third floor faster than they ever had before. Riddle really was fond of this room. Harry suspected she preferred the Room of Requirement, but that was clearly not a secret she was willing to share with her lackeys. Why she had decided to offer it to Harry in the first place still baffled him. It was an invaluable study guide and an excellent place for practicing magic. Throwing something like that away so casually just for the opportunity to befriend Harry still seemed odd. Riddle always seemed to act pragmatically and with her goals in mind, but Harry still failed to see what that agreement had accomplished. Merlin, he was sick of being perplexed by Riddle.

Apparently, so were the others, for they all watched Riddle expectantly. Harry wondered why for a moment, then it hit him — they were all hoping she would reveal herself as the Heir of Slytherin. He wanted to believe they only wished to hear so because it would dissuade their worries, but he knew that was untrue. Members like Lestrange, Rosier, and Dolohov would probably hail this attacker as a saviour so long as they continued attacking only muggleborns. The thought made Harry sick.

Riddle just watched all of them, waiting for someone to speak. Harry realized what she was doing. She was curious, testing them to see who would ask first. It would show her who was the boldest or, perhaps, who was the most impatient. It was another sign of how far he had come. Back in his own time, he would never have recognized a social trap like this one, but here, he had picked up on it in seconds.

Mulciber, apparently, did not. “So…” he asked, letting his question hang in the air.

Riddle just raised an eyebrow. “So what, exactly, Silas?”

“Well,” he said, beginning to shuffle, “it was you, wasn’t it? You attacked Myrtle?”

Riddle scowled. “Are you that imperceptive, Silas?”

“Imperceptive?”

“I have treated Myrtle well and suffered her all year. I have shown her nothing but kindness and patience even in the face of Abraxas and his threats. Why would I suddenly shift my stance and attack her?”

Mulciber looked stumped, but Rosier was not. Now that one of them had spoken, it appeared that the flood gates had opened. “It would be a sound diversion. Everyone would say the same thing you’re saying now. They would all remember you being patient and kind when it was all just a setup.”

“A setup for what, exactly?” Riddle asked, eyes now fixed firmly on Rosier.

He held her gaze much more effectively than Mulciber. “To begin purging the school of muggleborns as the myth says. Slytherin’s heir was supposed to open the Chamber of Secrets. There’s only one person at Hogwarts I know who can speak Parseltongue.”

There was a general din of agreement all around the circle, but Riddle’s posture remained unchanged. “Why would I have any interest in purging the school of muggleborns? Need I remind you I am not pure of blood myself?”

Rosier’s expression darkened before his cheeks flushed. Harry became intrigued. Never before had this group discussed Riddle’s blood status so openly. Now it was clear they really did just do their best to ignore it. It must have been an uncomfortable truth for these students to know that the one they were following so completely was technically a rank below them.

“You can’t play innocent with us,” pressed Lestrange. “Any time you speak of the muggles, you sound just like us. You know they’re a stain on this world.”

“The muggles have no bearing in this conversation.”

“But—”

“Magic is magic, Romulus. Would you deny I am more skillful than any other student you have ever seen?” No one did. “I am a halfblood.” Riddle turned her attention towards Harry for the first time. “Harry is a fourth year and he duelled Antonin to a stalemate despite his practice. He is also the fastest improving member of this group. As I’m sure you’re all aware, he too is a halfblood.”

“What’s your point?” Rosier asked with narrowed eyes, looking recovered from his earlier break in composure.

“My point is that there is very little differentiating muggleborns from purebloods, no matter what you have been taught. What is important is the difference between muggles and magicians. If I could shatter the connection between our two worlds with a snap of my fingers, I would.”

“But muggleborns are a link,” argued Lestrange, “they try and impose their traditions upon us.”

Riddle waved a hand. “They will never have true success doing so. Let them try, let them fail, it matters very little to me. The important connections between the worlds cannot be shattered by purging Hogwarts of its muggleborns. That would not stop the muggle weapons killing witches and wizards, it would not stop the abuse of magical children, and it would not destroy the risk muggles pose. I gain nothing from purging the school of muggleborns, so I will tell you all now that I am not the Heir of Slytherin.”

Harry watched Riddle’s face for any signs of insincerity, but he could find none, but that couldn’t be right. Despite the problems with the theory, Riddle being the Heir of Slytherin and attacking with Cerastes was the only thing that made sense. Surely no one else could be capable of a feat so similar to the attacks Harry remembered. It was all too convenient.

Yet Riddle’s logic was iron-clad. She was a halfblood who despised muggles. She made no illusions about that. She spoke candidly about the vitriol and even outlined some of the reasons why it existed. This had always been something that puzzled Harry about Voldemort. Why had he risen against muggleborns? It had never made any sense to him. Perhaps that was why Riddle’s arguments were swaying him. Was Harry trying to use irrelevant foresight and justifying her deception?

He frowned. If Riddle was the Heir of Slytherin, she was not only lying to him, but to all of her lackeys. It was not a lie they liked, either. Harry could see the tension in all of them and knew instinctively that Riddle had said something foolish. She had to know that, yet she had said it anyway. She had no reasons to lie about this sort of thing to these people. Perhaps she only did it because Harry was there, but even that felt flimsy. Why go through the effort? She knew how much he liked wandering off — she could easily have allowed him to do that at any time. That way she could have held this meeting without him and spoken openly.

Damnit! Harry had jinxed himself. He had thought just minutes ago this whole thing was about as complex as it could get, but his cynical side had been right — Riddle really had found a way to make things even more complicated.

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Back in the present…

Almost two weeks had passed since that meeting and Harry still had yet to make heads or tails of anything. It was all such a convoluted mess. There was contradicting evidence everywhere and Harry was unsure what to discard and what to believe. It was like working his way through a house of mirrors but instead of bumping his head against glass, his missteps had the possibility of sending him and the magical world plummeting into a void of destruction and despair.

How he yearned to just question Cerastes. Harry’d had much time to think, since slipping away these past two weeks had been next to impossible. There had been a time when he had genuinely considered demanding Cerastes to answer him. His logic had been sound. Everything he knew indicated the basilisk was completely subject to the whims of whomever its master was. Cerastes had served faithfully all year and, as far as the snake knew, Harry was its master.

But that was where that plan crumbled. If Riddle had somehow gained access to the Chamber of Secrets, Cerastes may now know the truth about him and the falsehoods he’d maintained. The basilisk would now obey Riddle, which meant it was unlikely to answer any of Harry’s questions. He was wary of going back to the Chamber of Secrets at all, but he had forced himself to descend. His instincts said Cerastes was fond of him. He doubted the basilisk would hurt him even if it sided with Riddle. Not unless she explicitly told it to, but if Riddle wanted Harry dead, she could have killed him herself.

“It has been longer this time than any other,” Cerastes hissed when Harry entered the chamber.

“There was an incident not long ago that forced the school into chaos. It made slipping away from the usurper difficult.”

Merlin, he really hoped Cerastes was on his side. He trusted the snake, but how could he read someone or something he couldn’t even look at? That would probably make it laughably easy for the basilisk to deceive him.

“Anything troubling?”

“Yes, but the chaos I was talking about isn’t as worrying.” That was, of course, a lie, but Harry would not be speaking about that particular event and his suspicions surrounding it. “One of my best friends hasn’t spoken to me in weeks, all because the usurper revealed her power and now my friend is afraid of being near her.”

“Then your friend is a coward who never deserved your fondness.”

Harry grimaced. “I’ll be the judge of that, thank you.”

“Of course, master. I was only advising. I will believe as you do if you command it.”

“Believe as you like, but I’d like any advice to be about how I can repair the relationship.”

“Snakes are not good at these sorts of things. Relationships mean little to us.”

“That wasn’t what I meant, I knew you wouldn’t be of any use there.”

“Then what was it you wanted?”

“To give you the details and tell you of my suspicions. People may be beyond you, but you have always read situations well. I want a second opinion.”

Cerastes’s next hiss sounded almost excited. Damn basilisks and their lack of empathy — he had ignored Harry’s distress entirely in favour of revelling in the praise.

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March 19, 1943
Albus Dumbledore’s Office
9:12 PM

Friday evenings were both extremely busy and extremely stressful. Harry usually went from dinner back to the common room, where he would hastily try and finish as much of the weekend homework as he possibly could. He would then make his way up towards Dumbledore’s office for their weekly Transfiguration lesson before finally meeting up with Riddle to discuss Ancient Runes.

Despite the stress and tight schedule, Harry enjoyed this part of his Fridays. Every time he finished another one-on-one lesson with Dumbledore, his confidence soared. Transfiguration continued to come easily to him. He had long ago managed some small feats with human Transfiguration and was now working on larger, more significant transformations.

Tonight, Harry had transformed his legs into a pair of flippers. This had taken him two lessons to finish, but Dumbledore beamed and Harry felt pride so strong it had only ever been rivalled once before — that being when he had beaten Charlus for the first time and watched the older boy’s wand soar towards him.

“This is truly exceptional,” Dumbledore said, reverting Harry’s body back to normal with a wave of his wand. “We may need to reconsider our goals for this year.”

“Reconsider, Professor?”

“I suspect that by the year’s end, you will have reached the level I would expect of any NEWT-level student. I think we may even be able to push further.”

Harry bit his lip as he thought, wondering how perceptive or suspicious Dumbledore could possibly be. Did he dare ask this? Did it show his hand too directly? It probably did, but at this stage, Harry felt as though his options were scarce. He really did need every advantage he could get.

“Is something troubling you, Harry?” Dumbledore asked. “Some adverse effect of the transformation, perhaps?”

Harry shook his head. “No, sir, I was just thinking.” He hesitated. “Professor, with the war going on and the attacks inside the castle, do you think it would be possible for anything after the curriculum to focus on combat? Like, how Transfiguration could be used in a duel?”

Dumbledore took a step back and studied him. “There has only been one attack in the castle thus far. That is discounting the unfortunate accident involving the acromantula, but I suspect it is unrelated to our current plight.”

Harry agreed. Hagrid had likely just lost control of Aragog and neither of them was capable of what had befallen Myrtle Warren. It had now been almost three weeks and she remained unmoving in the hospital wing, with the professors and the matron all thoroughly baffled.

“Yes, sir, but most people think there will be more.” Harry watched his face closely. “I think you believe that, too.”

Dumbledore sighed and sat back in his chair. “I would like to believe otherwise. There is enough conflict in the world right now without it touching a school.”

“But you can’t deny it?”

Dumbledore seemed to consider something. “The attack was very reminiscent of a legend that has floated around for some time.”

“The Chamber of Secrets — enemies of the heir could refer to the Heir of Slytherin.”

“Indeed,” Dumbledore said, raising an eyebrow. “May I ask how you came across this particular tale?”

“I read a bunch about Hogwarts before coming here, just so I wasn’t shell shocked. Hogwarts, A History talks a little bit about the Chamber of Secrets.” Despite Harry’s new academic focus, that was one book he had still yet to read. Hermione had, though, and Harry remembered her telling him and Ron about what that book said regarding the Chamber of Secrets.

Merlin, that was odd. Thoughts of Hermione and Ron had once torn Harry apart, but now? He missed them, but it was a dull, aching pain. It persisted even as he continued to speak, but it was lost in the background and quickly faded away to nothing at all. That made a part of Harry very sad, but most of him was grateful such thoughts would not damage him the way they once had.

Dumbledore nodded. “I suppose it would, yes.”

“So you think the person attacking students is the Heir of Slytherin.”

“I think it’s a possibility that cannot be discounted.”

Harry had to remember that, in this time, Dumbledore was still only the Transfiguration Professor. He might have generally been more open, but discussing something like this was above his station. Harry imagined he could get in grievous trouble if he told him too much, so he allowed the conversation to move on as his mind moved on to other problems.

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March 25, 1943
The Restricted Section
10:24 PM

The common room had already begun emptying by the time Harry slipped out. Riddle was on prefect patrol duty and many of the other Slytherins were either sleeping or studying. Spring break was fast-approaching and with it would come their final set of major tests prior to the end-of-year exams. This was the second most important time of the year in terms of their grades, so the castle felt quieter now than ever.

Harry had watched Riddle’s group closely for months and, by now, gained a relative understanding of how most of its members spent their time. Whilst the likes of Lestrange and Rosier might well be in bed on nights when Riddle was absent, Cassiopeia most certainly would not be. She was like Riddle in that way. Oftentimes, no one would even see her retreat to the dorms. She would just be there the next morning.

Finding her almost half an hour after curfew was not something Harry looked forward to, but it was necessary. If he was right about the entire situation with Dorea, this was the only first step. Even Cerastes had agreed with his read on the situation and had helped him devise the only plan either could think of.

Harry neared the library’s door and paused, glancing down the corridor before removing his wand. This was going to be a true test of how far he had come in other subjects, not just Transfiguration. He had been trying to make this spell work for some time, but it had always proven difficult. Tonight, it had to work.

“Illūsiōnum.”

Harry felt no physical change, but he knew at once the magic had taken effect. Merlin, magic sensing had become surprisingly useful. He cast a Supersensory Charm on himself so he could listen to whatever was happening inside the library. No one appeared to be near the door, so he cancelled that spell, cast a Silencing Charm on the door’s hinges, and stepped inside.

Many of the candles and torches had been extinguished with the passing of curfew, so the library was plunged mostly into darkness. It was so complete near the door that Harry mentally cursed before recasting the Supersensory Charm simply so he could see where he was going.

He crept towards the Restricted Section, where he heard someone breathing. As he drew near, he held up his pass from Slughorn and walked straight through. The librarian may not have been here, but there were wards guarding the section’s entrance. If he went through all this trouble just to find another student sitting where he presumed Cassie to be, he would be livid.

“You can reveal yourself,” she said as he drew near. “I know you’re there.”

Harry had felt the ward coming, but had detected no ill intent. He had decided it was likely just there to alert Cassie if someone drew near. Disillusionment Charms did not fool something like that, but they didn’t need to. Harry was not here to hide.

He let his spell fall and stepped towards her. For a moment, she actually looked surprised. “Pavonis?”

“Black.”

“I wouldn’t have expected it to be you.”

“I would have been surprised if you had. I wouldn’t have expected me to be sneaking up on you, either, but here we are.”

“You want something then?”

“I have a small favour to ask.”

Cassiopeia raised an eyebrow. “A favour? I wasn’t aware we were at the stage of asking favours from each other.”

“I do mean small.” Harry reached into the pocket of his robes and withdrew a simple envelope, holding it out. “I wanted to ask if you could deliver this message to Arcturus Black.”

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Author’s Endnote:

A number of reviews have voiced displeasure about how long it’s taking Harry to realize Riddle is not the same person he knew in his time. I must admit this surprises me. He has known her for just over half a year. That time has to contend with three years of him hearing just how awful Voldemort was, not to mention the fact he murdered Harry’s parents and confined him to a childhood he loathed.

The shift will happen, but if you expect all of that to be undone by a single event, you are reading the wrong story. The time is coming, but it has not arrived yet. I want character development to feel earned, not just to happen because it’s convenient for the plot.

I absolutely respect different opinions, but thought I would just give mine here. It sounded much more efficient than individually responding to everyone sharing similar thoughts.

I do appreciate the reviews, though, both positive and negative. Keep those coming because there have absolutely been some whose contents have been helpful.

Like I said in the opening AN, I will be recording a podcast with the author of A Cadmean Victory. If you want to ask us any questions, submit them on my Discord server, in a review of this chapter, or in a PM.

Please read and review.

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