Warnings: Torture, Dark magic, references to m/m sexual acts.

Disclaimer: All Harry Potter characters herein are the property of J.K. Rowling and Bloomsbury/Scholastic. No copyright infringement is intended.

Author Notes: Written for the nextgendarkfest at LJ. Thanks so much to lilmisblack for the shine of the brilliant beta job, to the prompter for a truly inspiring, clever prompt, and to snarkyscorp for running another wonderful fest. I'm sorry that I caused extra work.

The prompt: There was this Dark Wizard who was extremely hard to kill, because he hid pieces of his soul everywhere, in a young boy and a girl, for example. Is it a Good Idea for those two to marry and have children? And then they produce a son who, like his father before him, looks like a younger version of said Dark Wizard (except for the eyes).

The Chamber Will Open Again.

Lily Luna Potter stood in front of the wall which dripped with red paint (was it paint?) beside the library. She and her friends had paused there between classes several times a day since the letters had appeared almost two weeks before. Like everyone else at the school (except one, perhaps), she wanted to know who had written it, and whether they were serious.

The official response from the staff was that it was a particularly sick prank aimed at scaring the firsties. Well, if that was what it was then it had worked, and not just on the nervous eleven year-olds. Lily was in Fourth Year and she didn't know anyone who wasn't on edge now (though one of them might have been pretending). The school was swamped with rumours and distrust. Huddles of students all over the building went over what had happened the last time the Chamber of Secrets had been opened – when Lily's parents had been inside it.

The staff wouldn't tell anyone whether the words had been written in paint, or blood, or something else entirely, and Mr Goyle, the caretaker, couldn't clean it away.

Lily looked away from the wall to find that her friends were looking at her oddly again. She nodded, and they continued together to History of Magic. She would have liked to spend more time studying the message, though she was already sure that there were no clues anywhere near, but she knew her friends wanted to get out of the corridors where they felt exposed, and nobody dared to walk around on their own these days.

Opposite the door to the History of Magic classroom they stopped again, fascinated by the words which had appeared painted in green five days before:

Slytherin's Heir Walks Amongst You.

Mudbloods Beware!

The moment the message had appeared, speculation had raged. Every House suspected members of every other; every child privately accused their least favourite teacher; several names were whispered over and over again.

They had been ordered not to touch the green letters; there was still a chance that they might have been written in venom.

"We're about due the next one," someone murmured flatly. It was unclear whether they meant another message or another death. Three Muggle-born students had died already. Their bodies had been discovered in various secluded parts of the castle and its grounds. Staff claimed natural causes, accidents, coincidence.

The girls turned and went into the classroom. Professor Lupin wasn't there yet. She had got used to calling him that now, though two years earlier when he had started teaching - when Headmaster Flitwick had finally exorcised Professor Binns - she had nearly called her god-brother Teddy during a lesson.

As she walked to her seat there was hissing chatter all over the place. When she sat down in front of a group of Ravenclaws they pointedly stopped talking, but she had already heard them:

"His mother was possessed through the diary last time, and his dad was a fucking Horcrux. Everyone knows that."

"Right, and if you look at those photos of a young Tom Riddle -"

"Everyone says he looks like his father, which he does, but both of them look like Volde -"

"Don't say it! Don't say the name, just in case it's him come back!"

"It's not. He's dead. It's a different heir. It's -"

Lily's head hurt. She'd heard all these arguments before, knew full well who they were talking about. She'd never got on with her brother Albus particularly well, but she couldn't believe he was evil. There were many people now saying that he was Slytherin's heir, but she didn't believe it. Did she?

Albus certainly had a secret. He had always been vicious at protecting his privacy, more so in the last few years. He was a sullen, malevolent phantom over school holidays, mostly staying in his room and refusing to say where he was going when he did go out, arguing with their parents and ignoring her and James. He was a teenager with a lot to deal with and a bad temper. They all had a lot to live up to, a lot of Press attention, and parents who woke the household regularly with their nightmares. Albus reacted badly. That was all it was (was it?).

"Take no notice," Shona Jordan said as she sat down next to her. "Anyway, everyone knows it's Professor Patil. She gave my last essay a really low mark. That's a sure sign!"

"If you'd been listening in her Divination class you'd've seen that coming!" joked Hugo from across the aisle.

Lily tried to laugh along, but the sound stuck in her throat. "Seriously, though," she said. "What do you lot think to the Scorpius Malfoy theory?" Personally, she liked it, because it was nearly as popular as the Albus Potter theory. Also, she couldn't stand Malfoy (well, she couldn't stand the fact that he didn't think she was worth talking to).

"It's not a bad one, actually," Shona replied. "It would make sense if it was a Slytherin, and his family's all Dark on both sides. The bad goes back centuries. He probably is related to Salazar Slytherin somewhere along the way."

"He is. I've been researching," said Lorcan Scamander.

"Of course you have." Hugo rolled his eyes.

"Well, there's a pretty good chance that whoever's calling themselves Slytherin's Heir actually is -"

The order to shush swept through the room as Professor Lupin entered it.

.~~~~~~'

The Chamber Is Open.

Time for a sacrifice.

Huge black letters covered the back wall of the Great Hall. Students were hurriedly ushered away to eat in their Common Rooms. Albus wasn't there.

"Settle down," demanded the Prefects. "It's a prank!" Even they didn't believe that any longer.

"It's open?" Hugo asked. "What does that mean? Last time it meant that -"

"I'm sure it's fine," Shona said briskly. "They'll count heads, make sure nobody's missing, and then we'll know that nobody's been dragged down to -"

"Albus should be here," Lily whispered.

They looked round quietly.

"It doesn't necessarily mean he's been abducted." Hugo sounded unsure.

Nobody said it, but they all knew. It might mean something even worse. Lily tried to stop the hot tears which erupted from her eyes.

.~~~~~~'

She couldn't sleep. She doubted that many of the girls behind their bed curtains were sleeping, either. How could they? The teachers wouldn't tell them anything. She had to know what was going on, and she was the only pupil who could find out.

She was the Potter child with the Parseltongue inheritance. Her father had always warned her to keep that a secret; it was a Dark gift, an inheritance from the Dark Lord himself. Nobody trusted a Parselmouth. Even her revered father had to suppress that ability.

Everyone knew, though, that he had used it to get into the Chamber last time. She knew just what to do, so she snuck out of her bed, under her father's cloak, in order to find out what was going on.

She made it past oblivious prefects and into the bathroom, where she called out her hisses to open the passage. There was no light in the Chamber and she did not dare to cast Lumos . The air was stale and full of dust from the rubble all over the floor. She slipped on sticky liquids she chose not to investigate. Eventually, after hours of scrabbling blindly, she heard footsteps. She stood still to listen hard trying to pinpoint the direction they came from. She moved her shuffling feet towards the sound, and soon another reached her – a low, crazed laughter.

A sudden blaze of light lit up the space, then faded as somebody screamed. In that brief moment, she saw a high-ceilinged room with walls of rock and a floor littered with boulders. On the other side of one of those lumps of rock she saw a face she knew – her brother's.

Her blood froze and then rapidly boiled, her stomach churned. Albus. It was Albus. It wasn't him screaming, but much more than that she could not see. She edged numbly towards the place where the boulder had been in the hopes that if there was another flash of light, she would be able to see around it. She could hardly believe it. "Albus, my brother, the evil heir," she said in her head, but it did not feel like a truth; she could not absorb that fact. Albus had opened the Chamber? Albus had left the messages? Albus had killed students?

The next flash of light was blue-ish. The scream which followed it was Albus' this time, and it was accompanied by a louder laugh. Her brother's body was illuminated, and it was tied to a chair. She saw his face and it was agonised.

She began to feel relief and then stopped it sharply. If her brother was not the Heir of Slytherin, then he was the Heir's victim. The sacrifice. She edged closer, clutching their father's invisibility cloak, trying to work out a way she could rescue her brother from this evil maniac.

She had seen another shape, another body. She moved silently, getting herself into a position where she would be able to discover more next time. She hoped for another burst of light, while at the same time dreading it, because each time she could see, someone ended up in pain.

The hysterical laughter eventually died down, becoming again a low chuckle. The footsteps resumed. A bolt of white light cut through the dark, downwards, illuminating blood-splashed stone and then her brother's feet – bare, wound round with chains – before bouncing off the floor and onto a face. The face was twisted, but it was unmistakeable: pale, sharp features, with fair hair sweeping across its forehead. So, the Scorpius Malfoy theory had been correct? Why not? He was a Pureblood, a Slytherin, the heir to a family which had long believed in Wizard Supremacy. He strode about the school as though he owned it. She hated his arrogance. (She kind of liked too). Her father had been wrong when he had suspected Scorpius' father of being Slytherin's heir, but this time things were different.

"So, here we are boys." It was a voice which sounded familiar, but it was so laced with venom that she could not recognise it. "The Chamber of Secrets." It might have been Scorpius Malfoy's voice; it might not.

She heard panting and grunting, wished she could see.

"Who ... who?" That was her brother. It was thickened. Perhaps he was gagged. His mouth could have been full of blood. Or broken teeth. Her mind sprinted between impossible plans as she felt along the floor with her feet, trying to find a clear path. She couldn't work out how to overcome a powerful wizard she couldn't even see.

" Lumos ." As if in answer to her need, light sprung from a wand a little way in front of her.

The whole scene became clear then. Scorpius Malfoy's grimace was one of pain. He was no more the master of the Chamber than Albus was, rather he was chained to its wall, his arms held aloft, his bare chest marked by angry red welts. A few feet of stained stone floor lay between him and Albus, and in that space stood a hooded figure.

"Who am I, Albus? Don't you recognise me?"

Albus lifted his head and strained it round. The hooded figure dropped the wand, which stayed lit, and pulled another from his sleeve. He pointed it at one, and then the other of his prisoners, and declaimed, " Crucio! "

Lily watched the agonising pain pass through the bodies of the two boys. She closed her eyes against the sight. (Not as brave as she'd thought she was, then). She had to find a way to stop this. She had two students to rescue now. She thought, briefly, of her parents, of how they had been down in this hellish Chamber once before, of how her father had saved her mother. She looked at Scorpius Malfoy, his head slumped on his chest now, his breathing laboured as he recovered from the pain. Broken. All his brittle arrogance had been pulled violently out of him. She could be his hero, his heroine, his saviour. And then he would be able to remember her name. Her parents had married eventually ...

"By the way, thanks for the wands, boys," rasped that voice she almost knew. "They'll show some interesting spells on them when they eventually get examined. Except, of course, that only one of them will remain once I've finished with you. I'm going to destroy the other one. Which should it be? Who'll be my victim and who'll be my scapegoat? You're the leading contenders, you know. Up there in the school they all suspect the Heir is one of you two. And nobody's even mentioned me." He chuckled that dangerous, low chuckle again. His hands went up to his hood. Both boys lifted their heads, their curiosity winning out over their pain and exhaustion. Lily strained forwards, too. "Nobody suspects poor, sweet Professor Lupin," he said as he revealed his face.

The noises the boys emitted were wordless, incredulous, devastated. Lily bit her lips together to avoid betraying herself. Teddy Lupin, her Teddy Lupin, the hero of her childhood, stood before her, brandishing a wand, dressed in black robes, torturing two prisoners.

"Poor, tragic Professor Lupin, orphaned by the war against Voldemort. Who would expect him to be a Dark Lord? But, you know what, young Scorpius?" Teddy stalked towards the chained young man whose face was crumpling as though he were about to cry, "I've got the same blood as you have. I'm a Black, too, and the Blacks can trace our lineage back to Salazar Slytherin. My blood may not be pure, but nor was Lord Voldemort's. He hated his Muggle father, just as much as I hate my half-blood parents - blood traitors who abandoned me as an infant, who laid down their lives for his father." Teddy pointed his wand at Albus. It trembled for a moment. The whole room held its breath. Then Teddy whispered the curse, and Albus' body was wracked with pain again.

Scorpius' eyes darted between Albus' twitching, screaming, bound form and the face of Teddy Lupin.

"Sorry to disappoint, Scorpius. Did you think we had something special?" Teddy raised his wand, and Albus went from screaming to a pathetic keening. "I knew you would be my second victim from the moment you walked into my classroom. Your family never deigned to have anything to do with me when I was growing up, despite our shared blood. Oh, but I could see that look in your eyes, that worship." He lifted Scorpius' chin with the wand. "Yes, sweetheart, second choice. I'm so sorry, did you think you were the first?" he asked in a mock baby voice.

Then Teddy stepped back, making Scorpius' head drop with a violent suddenness. Teddy threw back his own head and laughed a long, loud, mad laugh. Lily tried to use the noise to cover her footsteps as she edged forwards. Her foot hit a stone, which shifted and she nearly fell. She couldn't risk revealing herself; she stood still.

Teddy strode the few steps to Albus in the old, ornate, broken chair, and bent down. He ruffled Albus' hair, making the boy flinch. "Young Albus here was always going to be my first choice. He looks so much like his father, after all - his father who murdered the best hope Wizardkind ever had. I will rebuild the legacy of purity. And on the way, I will destroy that man!"

Lily felt hot tears prickling her eyes. Her parents had always made Teddy welcome, she couldn't understand why he was acting like this. They had looked after him almost as though he was their own son. (Perhaps the answer lay in that 'almost' for a boy who had no parents of his own?).

Teddy's hand tightened on Albus' hair and he pulled his head back. "Oh, and you always did love me, didn't you, Albus? I knew you would do anything I asked of you. You looked up to me with such worship in those blinkered, wet eyes of yours. Ah, my pretty, stupid boys." He let go of the hair. "So much more malleable once you'd had your cocks in my arse."

Both heads shot round to look at the other boy, then at Teddy. Albus' mouth dropped open in shock. Teddy laughed his cruel laugh again.

"Oh, dear. You thought you were the only one?" He looked from the black haired boy to the blond.

So that was where Albus had been going all the times he wouldn't say…

"Bastard!" Albus managed to spit out.

Teddy grabbed hold of Albus' lips. He dug in his nails and twisted. Blood dripped onto Albus' chin.

"Language!" Teddy admonished in a whisper. "What would dear Mummy say? Her precious little prince using bad words like that?"

Then he bent his head down in a parody of a kiss. It must have been all teeth judging by Albus' muffled cry and the state of his mouth when Teddy pulled away.

Scorpius' lip quivered. Teddy strode casually over to him, licking blood from his lips. He fingered the wand. "Which one the scapegoat and which the victim, I wonder?" He bent to retrieve the Lumos -casting wand on the floor. He looked at Albus and ran his fingers absently over Scorpius' naked chest as the boy stared into his face, moisture glinting in his eyes. "You both thought you had owned me, bettered me in some way, didn't you? You thought that I belonged to you because I'd allowed a small and unimportant part of your bodies inside a little part of mine. And after that, I knew you'd go wherever I told you, and do whatever I wanted."

Lily raised her wand beneath her cloak. She would try Expelliarmus and see what happened. Suddenly the light went out.

"All dark. It's just because I'm swapping wands. Get ready for some pain, Mr Malfoy. Already the school is full of fear and panic. Three are dead. Three Mudbloods; contamination that I have purged. The same fate awaits the rest of those magic-stealing Muggles."

The Chamber filled with light again. Startled, Lily jumped. All three men looked in her direction, and she froze with terror. They shook their heads after a few seconds as though they hadn't seen anything. (Of course they hadn't, she had the cloak on. She had forgotten).

"Meanwhile," Teddy continued, running his wand over Scorpius' concave, lightly haired belly. "I need a body to lie in the Chamber, and another to take the blame. " Sectumsempra ."

Scorpius screamed and his body twisted to try to curl in on itself protectively. His trapped wrists and ankles prevented that. Long, bloody slashes appeared across his torso. Lily felt bile rise in her throat, but Teddy looked on with detached interest.

"That is a nice one." He cocked his head to one side. "I always wanted to try that one." He looked over at Albus' horrified face. "And I did that with your wand, Al. Which means that if I make you my scapegoat, nobody will believe that it wasn't you who did it. Clever, huh?"

Albus shook his head violently. Teddy chuckled, then swapped the wands between his hands theatrically. He cast Lumos with Albus' wand, and doused the light on Scorpius'. "Your turn." He chuckled. "Ready? Serpensortia !"

A large snake sprang from the end of the wand, fangs bared and dripping with venom.

Before she had thought, Lily found herself shouting out " Stop! Don't attack! " in Parseltongue. All at once she finally an edge, she had a weapon. The snake reared back and dropped to the ground. Teddy stared at it in confusion.

" Expelliarmus !" she called out while his attention was diverted, making sure she wasn't speaking Parseltongue this time. The three wands came flying through the air, and she stretched her hand out of the cloak to catch them. Teddy, Albus and Scorpius turned their heads in her direction. She grabbed the wands and suddenly, inexplicably, Teddy grinned.

A second later she was pulled backwards, the cloak dragged off her as all three wands were wrenched from her grasp.

" Petrificus Totalus !"

She was paralysed. She looked up, and it was Teddy's exhilarated face which looked down on hers. He grabbed her hair and pulled her painfully upright. She could feel his hand in her scalp, and yet she could also see him standing several feet away, between Scorpius' and Albus' wrecked bodies. His voice was at her ear when he said, "A Parselmouth."

"Even better," said the Teddy on the other side of the room. "I'd better go, then. I need to make sure a good few people see me in the Staff Room and patrolling the school, to get my alibi in place. Does it go smoothly?" he asked his other self.

"You'll get a chance to nobble Hugo Weasley early on. Take it. Otherwise he'll ask some awkward questions."

Teddy nodded. He bent his head briefly over Scorpius' chest and licked at the blood. Scorpius twitched but made no sound until Teddy bit into one of the deep lacerations. Then he screamed. Humming happily, Teddy pulled a small Timeturner from his sleeve. There was a scuffling noise as Albus tried to manoeuvre his chair, just edging towards the timeturner as though he was attempting a last heroic act. Then Teddy turned the hourglass and he disappeared.

A moment later, Lily's Petrified body was dragged over to where Albus and Scorpius were incarcerated.

"Sorry boys," Teddy snarled. "I've changed my mind. I'm afraid you're both going to have to be my victims. It seems all that earlier wand-work was a waste of time." He selected Lily's wand from the collection in his hand. "We'll have to cast a few more curses with this one." He pointed it at Albus. "Sectumsempra ! That one really is a beauty to watch."

He calmly turned Lily so that she was forced to watch her brother's agony. "Thanks for the cloak, by the way. That'll come in very handy. And it's a Hallow of course." He slipped the cloak into his sleeve. "Lovely. Now I have two victims and the perfect scapegoat, a Parselmouth." He kicked the now-docile snake out of the way. "It's a good thing you'd kept that quiet, young lady. Once I've exposed you by forcing you to reveal yourself, along with the history I'm about to put on this wand, everyone will be convinced that you are Slytherin's Heir. Leaving me free to clean up this school. Now ..." he pointed his wand at Scorpius.

Scorpius' face was wet with tears. "No!" He gulped. "Don't kill me. Kill her. I'll be your scapegoat. I'll do whatever you say. She's not even a Pureblood. We can rule together. Please. Don't hurt me any more. I'll do anything."

Teddy shook his head. "She's too good to pass up. Nobody trusts a Parselmouth." He turned to Lily. "It's a gift you got from the Dark Lord himself. Through your despicable father. Now, let's put it to a use Salazar Slytherin would be pleased with."

He pointed her wand at Scorpius and cast Crucio .