The stone steps from the dungeons were narrow and steep, with dimly spaced torches and damp flagstones.
Lily Evans climbed with her head still soaking in a cauldron of Draught of Living Death.
Slughorn had kept her hours past the end of the lesson. A half-finished sample sat on his desk, purple-black, a film of vapour drifting across the surface. The professor broke the stirring pattern down for her step by step, then produced an ingredient she couldn't name and said it was the trickiest of all the Draught of Living Death's supporting components. A grain too much and the whole batch was ruined.
Then he handed the ladle to her.
She stirred. The colour shifted from blackcurrant to a soft pale lilac, then bled away entirely until the liquid ran clear as spring water.
A perfect Draught of Living Death sat in the cauldron, without a trace of cloudiness or off-colour. When she tilted it, the potion slid clean down the wall of the cauldron, leaving no residue behind, carrying only the faintest cold bitterness of wormwood. Left to settle, it gave off a pearl-white shimmer so faint you had to look for it.
She dropped in a red mint leaf last. It touched the surface and crumbled into fine white ash, gone.
"Full marks at N.E.W.T. level, Lily. Third year, and this standard. You're the second student I've ever taught who could manage it."
Slughorn laced his plump fingers over his stomach, eyes creasing into slits, and pulled a thick leather-bound book from a drawer, pushing it across the desk. "Take this with you. Talent like yours shouldn't be left idle."
He was already stuffing something into her pocket while he spoke: a small packet of Crystallised pineapple, same as always.
She accepted it gladly. It was far too sweet for her, though, so she decided to give the whole lot to Marcia and Susan and not touch a single piece herself.
She was still smiling when she stepped out of his office.
The dungeon level was stifling. The fires had burned all evening, and the air hung thick with herbs and the scorched smell of cauldron bottoms.
Heat from the furnaces still clung to her face. She looped her scarf loosely around her neck, red hair spilling across the shoulders of her Gryffindor robes, and started up the stairs toward the higher floors.
Advanced Potion-Making and the packet of sweets went into her small purple satchel. She walked and thought about the colour of that potion, humming something tuneless, feet light on the steps.
Rounding the last flight, the humming stopped.
Someone was in the corridor.
The torches sat far apart, the light uneven, and between two pools of it lay a dark stretch of stone. Three figures stood there.
One was backed against the wall, spine flat to the stone, half an arm gone bone-white under a crust of frost. Sallow face. Greasy black hair. Shoulders drawn in tight.
Severus.
Facing him stood a boy with hair sticking up in every direction and glasses on the bridge of his nose, wand raised high, the tip nearly touching Severus's cheek.
James Potter.
A third leaned against the wall further along. Black hair, longer and smoother than James's, one shoulder propped on the stone, wand turning idly between his fingers, eyes on the other end of the corridor as though none of this had anything to do with him.
Sirius Black.
Lily stopped on the steps, and something behind her eyes caught fire.
These two. Again. Exactly like this.
She'd seen it too many times. First year. Second year. Third year. Twice already since term started.
Every time it was Severus on his own, cornered by these two, or these two and a couple of others, in some bend of some corridor.
Every time she ran over and shouted, and the pair of them peeled away lazily, tossing something ugly over their shoulders as they went, and were back the next day.
And every time, shouting was all she could do.
Her hand tightened on the strap of her satchel, then loosened.
She knew perfectly well why shouting was all she could do. She couldn't beat them.
Potter and Black were the two roughest duellists in the whole third year, spells fast and accurate, and charging in would have accomplished nothing.
A shout, at least, made it boring for them. They'd break it up. Severus would take two fewer hits.
Two years of swallowing that. The same helplessness, over and over.
Watching Severus pinned against a wall, wanting to storm in and actually make them pay for it, and knowing better than anyone that she couldn't.
She looked down at her own hand. Opened it, closed it, opened it again.
Something surfaced from months ago.
She'd asked Regulus once why some people simply enjoyed hurting others.
He hadn't answered. He'd asked her a question instead: Do you want to be able to stop it yourself, next time?
She'd frozen. Her eyes had lit up, then dimmed, because she knew she couldn't.
But Regulus told her to trust him. And she did. More than she trusted herself.
Now that question came back.
This time her hand closed and stayed closed.
Everything she'd drilled this past year surfaced piece by piece. Empty classrooms, repeating wand movements at nothing, over and over. The dormitory after her roommates were asleep, a feather lifting quietly off her palm. A power cut at home, and a paper crane folding its own wings against the moonlight in the window.
Regulus standing opposite her, breaking every spell she threw, then saying, again.
Maybe this time would be different.
She drew her wand and climbed.
"Two on one." Her voice bounced clean off the stone walls from the top of the stairs. "That's the best you can manage?"
James turned. When he saw who it was, his eyebrows went up and the menace slid off his face, replaced by something loose and grinning.
His wand stayed level with Snape's face. "Well. Evans."
"Potter." She came forward, red hair swinging, green eyes catching the torchlight and burning with it. "Put that wand down."
"None of your business." He shrugged, wand drifting lazily back toward Snape. "I'm having a chat with Snivellus. That bothering you? Go back to your tower."
"A chat?" The heat rose straight up through her. "You call this a chat?"
"He's got a mouth on him." James lifted his chin, entirely unbothered. "You didn't hear what he said just now. He's asking for it."
Over by the wall, Sirius finally turned his head, gave Lily a glance that said he'd watched this exact scene eight hundred times and couldn't imagine what was novel about it, then looked away again.
She saw that look.
It made everything worse. One of them swinging, one of them watching, and both of them treating it like the natural order of the world. Bullying someone and sleeping fine afterward.
"Push off, Evans." James waved a hand like he was shooing a fly. "This is a boys' thing, and you're a..."
The sentence stalled. He didn't bother finishing it, just went blunter. "It's not your business. Push off."
"I think it's very much my business." She took another step, voice climbing. "Every time I walk past, it's you two doing this. You're not sick of it. I am."
"Sick of it?" That delighted him. His eyebrows went up and for the first time he looked her over properly, head to foot. "Evans, what's got into you today? You're spitting sparks."
His mouth stretched, and he dragged the words out on purpose. "All this for Snivellus? Your taste in friends is something else, honestly."
She stopped a few paces off, wand in hand, not pointed at anyone yet, the anger rising through her voice in layers.
"If you've got any nerve, let him go and find someone who can actually fight back. Jumping someone on his own, what does that prove?"
James laughed, glanced sideways at Snape, then back.
"Him? He wasn't sounding very outnumbered a minute ago." The contempt in it was undisguised. "Snivellus was explaining to me what it means to strut."
Her brows pulled together, lips pressed flat.
She'd known James Potter a long time. He'd been exactly like this since their first day.
Arrogant, loud, a complete git, always with a crowd orbiting him, always convinced the world was his playground.
The worst part wasn't the mouth. It was that he saw nothing wrong with any of it. Hurting people came to him as easily as eating and sleeping, and the angrier you got, the more he enjoyed himself.
"James Potter." She raised her wand and pointed it at him. "If your mouth were a bit worse than your talent, Gryffindor would lose half as many points."
He blinked, then broke into a grin, thoroughly pleased.
"Oh ho." He tilted his head, studying her. "So you can insult people after all, Evans. I thought your whole vocabulary was stop it and don't."
He kept needling. "Go on, give me a couple more. Let's hear what else you've got."
She glared, eyebrows knotted. "You think everything's a joke? You corner someone, two against one, and when somebody tells you to stop, you tell them to push off. Who exactly do you think you are?"
"I think I'm James Potter." He shrugged. "That answer work for you?"
"No." Her voice went up, and she gave him nothing. "I think you're an arrogant git who's never once been knocked off a broom, which is why you imagine nobody in the world can touch you."
His eyebrows climbed higher and he let out an exaggerated wow, glancing over at Sirius.
When he turned back, the grin had thinned a little.
"All right, Evans." The tone was still airy. "Dead set on being the hero today, are you?"
"I'm not here to be a hero." Her wand tip settled on him. "I just can't stand watching the two of you."
Against the stone wall, Snape's face twitched.
James caught it. He wasn't gifted at much, but his instinct for a fight was born in him.
His eyes narrowed and the clowning eased back a fraction, though nothing about him went serious. He'd only noticed that the Evans who normally shouted twice and went to fetch a professor was standing differently tonight.
"So what's this then," he said, grinning again. "You actually want to duel? Me?"
"Try it and find out." She held his eyes, green ones lit like struck matches.
By the wall, Sirius turned his head. He hadn't planned on joining in.
Snape's words were still circling in his skull. Knocking on the door. Those people. The last two years. He'd understood exactly what Snape had been talking about, and it was sitting in his chest like a coal.
Then Evans had appeared and going toe to toe with James. She used to only shout stop. Now she knew how to shove James's own mouth back down his throat.
And she'd actually drawn her wand. Actually looked ready to go through with it.
Bold of her.
Interesting.
The knot of irritation in Sirius's head loosened a little under all that novelty.
His eyes moved. A bad idea arrived, and the corner of his mouth curled with it.
He said nothing. He simply turned his wand a different way.
Lily's wand was already up, aimed at James.
A whistle split the corridor, sharp and bright, kicking a string of echoes off the empty stone.
Both of them looked toward the wall at once.
Sirius pushed off it, flashed James a grin that was pure spectator, and flicked his wand toward Snape. Silencio. Two flashes leapt from the tip, one after the other.
The first was red. It caught Snape square in the chest.
He slammed backward, skull cracking against stone with a dull thud. His wand jumped from his fingers and rattled away across the floor.
Before he could pull in a breath, the second spell hit. Petrification.
His limbs locked. He stood pinned to the wall like something nailed there, only his black eyes still moving.
James glanced back at Snape, then at Sirius, and laughed. "Nice timing."
Sirius put his wand away, settled back against the wall, and lifted his chin at James.
Floor's clear. Rest is yours.
Lily's face went scarlet. "You..."
She whipped her wand around to Sirius, voice shaking, breath coming fast, chest rising and falling. "Ambushing someone who can't even move. You must be so proud!"
He didn't so much as raise an eyelid, just slouched there, every line of his posture saying the same thing.
I'm not fighting you. James is. I'm here for the show.
James snorted, stepped forward, and put himself neatly between Lily and Sirius.
"Hey, Evans." He brought his wand up, tone light. "I'm your opponent. Focus."
Her attention snapped back to him.
And in that single stolen second, James moved.