Harry stared at the snake engraved tap, tracing the cold metal of the small, silver squiggle with his fingertip. 'Open.'

It remained quite still.

Myrtle giggled and drifted from her cubicle. 'It doesn't work if you don't speak to snakes.’

'I can speak to snakes.’

'Well, you were only speaking English.’ Myrtle flashed him a shy smile. ‘I never did say thank you for killing the monster. You avenged me, Harry.'

'Er, thanks Myrtle.' He edged away as she drifted within arm’s reach. ‘I — er, appreciate it.’ Harry pictured a particular fire-conjured snake in his head. 'Open.’

The tap shuddered and the sinks split apart to reveal the entrance. A thick layer of slime, grime, and sludge coated the pipe that curved down into the dark.

Myrtle cheered. 'That's more like it!’

She’s half-pretty when she smiles. Harry frowned and stamped that thought out. This is one of those puberty things, isn’t it? Come on, hormones, let’s not make me act like Dudley.

'It sounds the same to me,' he said. 'I can't tell if I'm speaking parseltongue just by listening.'

'That was definitely parseltongue. It sounded just like before.' Myrtle’s face fell. 'When he used to come here.'

'Sorry. I didn't mean to remind you.'

'That's okay, Harry. You weren't the one responsible. I blame Olive Hornby more than him, anyway.' Myrtle's face twisted into a grimace. ‘Stupid Horny, she got me killed.’

Harry pursed his lips at the slimy pipe. ‘I forgot about how dirty it is. Honestly, where’s Dobby when you actually need him?’ He sighed. ‘Probably out somewhere trying to harm or grievously injure another innocent child.’

'There are steps, you know.' Myrtle hovered over the entrance and peered into the pipe. 'The red-haired girl who spoke in his voice made steps.'

He spared the brown sludge a long look. ‘Definitely worth trying. Stairs.'

The pipe twisted away to reveal a rather dusty, dark staircase.

Harry followed a small set of footsteps down through the dust into the dark. Ginny's steps. His skin crawled as the silent gloom coiled round him. Poor girl.

A second door identical to the one he’d encountered on his last visit blocked his path. It opened at his hissed command and he stepped into the Chamber of Secrets.

Bones crunched beneath his feet as he strode forward. The giant snake skin sprawled across the floor; its green gleam faded to dull white. Beyond it, bright, iridescent poisonous green scales shone in the faint light.

Harry paced the length of it. How did I manage to survive that monster, let alone kill it? It’s at least seventy feet long! He drifted round to its mouth and held his arm up beside its fangs. They’re as long and thick as my forearm.

‘King of serpents indeed.’ Harry trailed his fingertips along its cold scales. ‘It‘s identical to the one I conjured, just much larger.’

A dark stain marked the stone close to its tail. Harry shot it a glare and stepped over it to stand before the giant bust. I wonder if I can open the door, too.

'Speak to me, Slytherin, greatest of the Hogwarts four.'

The mouth opened with a stony scrape.

Chill fingers seized Harry’s spine. There better not be another giant snake. Why did I open the bloody door?

'What a ridiculous way to open the door, it responds to virtually any command in parseltongue, you know.' A high, even voice echoed from within the bust.

Harry stared into the dark beyond the bust’s lips. Well, it’s not Tom Riddle. Riddle would never make fun of his own ostentatious phrasing.

'And no, I won't speak to you.'

That can't possibly be the voice of Salazar Slytherin. Harry eyed the water. Well, finding out is probably worth getting very cold and wet. Just. Still, if there were stairs…

'Bridge?' Harry grinned as a stone a serpent's tongue rose from the pool, extending as if from the mouth of Slytherin himself. He put one foot on the forked tip of the tongue.

'Oh, by all means come in,' the voice said. 'I'd love another visitor. My other company all turned out delightfully well. An insane reptile and an only marginally more sane child with delusions of grandeur.'

Harry strode across the bridge and into Slytherin's mouth.

Shelves of dusty books lined the circular walls, interspersed with odd magical instruments, and a carved marble basin rather like the one he’d often glimpsed in Dumbledore's cabinet sat opposite the door.

‘The other one stood there and gawped, too.'

Harry whirled round. The portrait of a young, formidable looking wizard dressed in green and silver robes hung over the door. A snake wrapped itself around his shoulders just below where his ebony hair hung.

'Well, you look sane,' the portrait mused. 'But the last one did too and look how well that turned out.'

'Who are you?' Harry asked.

'Portraits are named.' The dark-haired wizard sighed. 'I always hated children.'

'Salazar Slytherin… If you hate children, why found a school?'

'It wasn't safe for magical children to just learn their craft all over the place. Don't you know anything about the burnings?' The sarcasm sharpened to bitter disgust.

'Witch burnings?'

'Sort of. The muggles couldn't actually burn witches and wizards, but they got a fair few of our children after they were seen performing accidental magic. Burning children alive.' Slytherin’s eyes flashed. 'And they called us evil. Hogwarts was a haven for magical children. They were taught how to control and even hide themselves for their own safety.'

'You don't leave a basilisk that eats children in a school!'

'She was meant to sleep until the school was under attack,' Slytherin snapped. 'A basilisk is very hard to kill, especially for those without magic. Had anyone ever tried to get to the children here, she would have protected them with her life. It worked perfectly until my last visitor twisted my commands to his own ends.'

'Tom Riddle,' Harry muttered.

'Yes. Basilisks are renowned not only for their power, but their loyalty, too. She devoted herself to her creator and my command to protect the children from the outside world. Tom Riddle corrupted my creation and set her on the children who’d come from the outside world to learn here.'

Harry felt a small stab of pity for the serpent. 'It's a good thing she's dead, then.’

'Dead?' Slytherin raised an eyebrow. 'Who managed to kill her?'

'I did.’

'You are my heir, I suppose. You would be powerful.'

'I am not your heir,' Harry said.

I’m not going through all that nonsense again.

Slytherin took a deep breath and pinched the bridge of his nose. 'You speak parseltongue. It’s an ability I recreated and is tied to my bloodline. Only my direct descendants can speak it, and as I have no desire to ever see Tom Riddle again, that makes you my heir.'

'Sorry,' Harry mumbled. 'The school all thought I was your heir in my second year when the basilisk was attacking students. They blamed me.'

'You can't really blame them. You do speak parseltongue. I assume you're in my house?'

'Gryffindor, actually.'

Stolen content alert: this content belongs on Royal Road. Report any occurrences.

'Gryffindor!? What is my descendant, my heir, doing in the house of that reckless, moronic, immature excuse for a wizard? The whole reason I had to build this chamber was because that child of a man couldn't resist his urge to sabotage my work…’ Slytherin’s voice faded to a grumble. ‘And all Helga would do is laugh.'

‘That doesn’t sound like Godric Gryffindor.’

'Did you think he was a noble, brave hero?' Slytherin shook his head. 'That wizard never matured beyond the age of eighteen. He was an exceptional transfigurer, quite brilliant and very creative, but cursed with a child's sense of humour. Most of the things he did around this school were actually done by Rowena and I after the idiot injured himself trying to enchant things in overly complicated ways.'

'I'm quite good at transfiguration,' Harry offered. 'The hat did suggest Slytherin, but I chose Gryffindor.'

'Why would you do that? Who’d want to live in a tower when they could have a view out into the Black Lake?' Slytherin’s wand spurted white sparks and the snake retreated into his robes. ‘And Godric himself? That man had no sense. His precious griffons? Stupid creatures. About as smart as a cow, much deadlier, and far less useful.'

Harry stared at the ceiling until the muttering faded away. 'I'm Harry Potter.' He stuck his hand out to the picture.

'Salazar Slytherin. I can't shake it, but I appreciate your manners.'

'I think I have to go to class now.’

'How old are you?'

'Fourteen.'

Slytherin’s stare bored into his. 'Your eyes are older. You’re my heir, return here whenever you like. My library and study are yours, provided you're tidy and not as childish as Godric.'

'Thank you.’

Harry strode back over the forked tongue and jogged up the stairs, taking them three at a time until he stumbled into Myrtle’s bathroom. I’m probably really late for Ancient Runes.

He hurried past the Great Hall and down the corridor, catching sight of Professor Babbling doing her best to live up to her name amongst a gaggle of seventh years. Harry slipped past her to join Hermione in the front row.

The walls were covered in multi-coloured posters, the office door itself was wrapped in parchment and covered in tiny sections of text.

‘Sorry, everyone! Just catching up with one of my other classes!’ Professor Babbling bounced into the classroom and spread her arms. 'Welcome back to Ancient Runes! Happily, everyone survived from third year. We even have an additional student, one who needs no introduction.'

The students turned to look at him, his scar, and twisted back to face their smiling professor.

'I trust you've all brought your copies of Magical Hieroglyphs and Logograms.' Professor Babbling plucked hers off the desk and waved it over her head. 'As this is the first lesson, I'll allow you to recap anything you feel you need to or just get started on the material for this year while I chat with Harry.' She smiled at him and gestured toward the parchment-covered door. ‘Mind joining me in my office, Harry?'

'Of course not, professor.' Harry abandoned his well-thumbed textbook.

She led him into a small, cramped room with walls covered in a patchwork of large pieces of parchment. Runes and notes were scrawled all across it in a dozen different bright colours.

Professor Babbling waved her hand at the walls. 'My office is my playground. Now, if you don’t mind telling me, why did you decide to switch to my class, Harry?'

'I find runes interesting. It’s quite different to the wand magic I’m kind of used to and, if I'm being completely honest, Professor Trelawney was a bit too fond of predicting my death.'

'How horrible,' Professor Babbling said. 'I'm glad you’ve a genuine interest in the subject. This is a small group and we tend to move quite fast, so anyone not completely on board can get left behind.' Her gaze focused on something just past Harry's head. 'Back to class, then. I won't pass your concerns about Professor Trelawney on. Just between the two of us, I've never really had time for a subject as imprecise and vague as divination.'

Harry spared a glance at the wall as he left. A bright pink zig-zag and a small, neat paragraph of handwriting stood out of the rest. Sowilo. He touched a finger to his scar as he took his seat beside Hermione. Stupid Voldemort, just had to leave a scar in a funny shape, didn’t he?

He flicked through the pages of his book, underlining key parts with his quill and jotting the references down in the margin.

Time crawled by with the faint tick of the clock and the rustle of parchment.

'What did Professor Babbling want?' Hermione asked as the lesson came to an end.

'She just wanted to know why I switched to Ancient Runes and to warn me about how fast the class will move.'

'We do go fast, but if you're already ahead in transfiguration then you'll be able to redistribute your time and keep up.' She beamed. 'Why did you switch, then?'

'I told you. I got a bit tired of being told how I was going to die every lesson.' Harry shrugged. ‘It was kind of funny for a while, but then she started repeating her predictions and the novelty wore off.’

Hermione shook her head and rummaged through her bag. 'It's Arithmancy now. I've got the notes from last year somewhere in here. I thought you might like them.'

Harry accepted the thick stack of parchment with a smile. I’d prefer your notes from Ancient Runes, really. There’re no really long essays for Arithmancy.

He scanned the pages as Professor Vector arranged her students into a precise seating plan that seemed as much about having everyone sat in a symmetrical pattern as it did learning.

‘Recap lesson today.’ Professor Vector fiddled with the brim of her hat and glanced at Harry. ‘At the end, if you struggled with any of the questions on the board, stay afterward and we’ll go over them to make sure you’re all ready to start the new stuff.’

Harry pushed his glasses up his nose and jotted down the answers to the first two, then paused and read through the questions. Oh, that’s a bit disappointing. These are all just basic ones.

Hermione glanced up. 'Are you stuck, Harry? Professor Vector won’t mind if you want some help.'

He rolled his eyes. 'This isn't the sort of Arithmancy I'm particularly interested in. In fact, I’ve a nasty feeling that most of the interesting stuff isn't covered until after OWLs.'

She chewed her lip. 'Advanced Arithmancy is supposed to be one of the hardest classes. Are you sure?'

'Of course. This is just the basics. Two-dimensional equations to help people understand what to do. After OWLs, they cover all the complex, interesting stuff. Two-dimensional equations are useless to describe magical patterns when any magic we fold into planes for warding or enchanting will be done in reality, an obviously three-dimensional construct.' Harry cocked his head. ‘Four, technically, since magic’s affected by time, too.’

Hermione blinked. 'I guess that does make sense, but you'll still need to know how to do this if you want to be able to do advanced things like that.'

Harry leant across and filled in the answer to the last question on her parchment. 'See, easy.'

Hermione huffed and scribbled out his answer. Harry returned to his doodling.

He’d just finished adding scales to the head of his Arithmancy basilisk when Professor Vector stood up and added the answers to the board with a flick of her wand.

One. Two. Three. Four. Five… Harry skimmed through the remaining questions. Ah, got one wrong, but that’s what you get for copying down the original question incorrectly.

Hermione stuffed her books back into her bag and stalked toward the Great Hall. Harry tailed her at a more comfortable pace, squeezing in between her and Ron midway along the Gryffindor table.

Ron squinted at him with bleary eyes. 'Divination was absolute hell without you, mate,' he mumbled. 'I had to partner with Lavender. She was so keen. It was no fun at all.'

Hermione picked at her food in silence, stabbing at pieces of lettuce like they’d done her grave personal injury.

'What's your horoscope, Ron?' Harry asked. ‘Any eternal glory in there?’

'Well, I'm not going to die, so it beats whatever yours would’ve been. Lavender mentioned something to do with fire, cups, and veela, but I think she was talking to Parvati about the Quidditch World Cup.'

Lavender hates quidditch even more than she loves gossip.

Harry patted Ron on the shoulder. 'You slept through the whole thing, didn't you?’

'It's so warm and stuffy. I don't know how anyone stays awake up there.'

Neville laughed. ‘No need for anyone to stir themselves, it’s History of Magic next. Even my gran says the subject’s a waste of time while Binns is still teaching it.'

'You know they say his body is actually still in his office from when he died and he just kept teaching as a ghost,' Seamus said.

'Aren't ghosts meant to have a reason to linger?' Ron asked

Seamus sniggered. 'Maybe he hadn't finished marking essays.’

'How does he mark our essays?' Dean wondered. 'He can't exactly touch them, can he?'

'Maybe that's why he never notices we don't hand anything in,’ Ron said, grinning.

‘Let’s go,’ Hermione snapped. ‘We’ll be late otherwise.’

Harry wandered after them, settling himself at the back of the class as Binns began to drone.

Heads began to drop as Binns floated through his desk, staring at the ceiling.

He glanced up from A Guide to Advanced Transfiguration as Binns drifted into the wall. Ghosts do not make good teachers. Especially not ones that were boring even when they were alive.

‘In this year, there were twelve hundred and forty two skirmishes between goblins and men.’ Binns’ voice echoed from the corridor outside. ‘The most in any single year.’

Why is this subject compulsory?

Hermione crossed her arms, dragged out some parchment and started on the first of their homework essays. Ron slumped onto his arm and started to snore.

‘Oi.’ Harry nudged him on the shoulder.

‘Whassat?’ Ron cracked open an eye.

‘Don’t snore so loud. I’m trying to read and everyone else is trying to sleep.’

‘Why’re you reading?’

‘Because I would very much like to be able to do some of this magic one day and even if we won’t start using this book for a couple more years in class, it’s still cool to read about.’

Ron grunted. ‘Fair enough, mate, but I’m just going to take a nap.’

Harry turned back to A Guide to Advanced Transfiguration and skimmed down the page to where he’d left off. Famous animagi. Stark warning about getting stuck in your newly transfigured body forever. Animagus theory. He read the first two lines. Wow, that’s a lot of things that could potentially go very badly wrong. Maybe this is something for a later date after all.

Harry swapped the book for his copy of Confronting the Faceless and propped it up on the desk with the index pages showing. There’re a lot of curses. He paused on one. Purple cutting curse adaption. Incantation lacero. That’s the one Barty Crouch Junior tried to use on me, that and the Cruciatus Curse.

Harry flicked to the section on Unforgivable Curses. Cruciatus Curse, best avoided, Imperius Curse, also best avoided, even if it’s the only one you can defend against. He traced the scar on his forehead, remembering dreams that always ended with a flash of bright green light. And the Killing Curse…

'Avada Kedavra,' he murmured.

I’ve always known the words to this one. He recalled attempting to correct a magician at one of Dudley's birthday parties when he’d been much younger, knowing it was wrong, but not quite knowing why. Strange, that of all the things I could’ve remembered from that night, it was that.