James Potter's eyes were wide, his jaw slightly unhinged. Behind him, Remus Lupin gasped, and Peter Pettigrew let out a short squeak before clapping a hand over his mouth.
Sirius stood in the corridor, his body rigid. His fingers twitched, instinctively curling toward his wand, but he forced himself to freeze.
Intervening to help outsiders against his own brother was dishonorable. But more than that, Sirius knew the truth: even if he drew his wand, he wouldn't win. And losing to his little brother in front of James would be a humiliation he couldn't stomach.
Severus Snape stared at the frozen red ribbon of light, then slowly turned his head to look at Regulus.
Lily Evans was still gripping Snape's sleeve, but she had forgotten the gesture. She was just staring blankly at the suspended magic.
Finally, Regulus raised his head.
He glanced at James with the same calm indifference one might show a piece of furniture. Then he looked at the red ribbon. His right hand still held his quill; his left hand held his wand.
He gave a minute twitch of his wrist.
The red light began to fade. It shifted from vibrant crimson to a dull rust, then to a ghostly transparency. Then it began to decompose. Like ice melting in fast-forward, the spell broke down into countless tiny red sparks.
The sparks swirled in the air for a brief moment before vanishing into nothingness.
The process was neither fast nor slow. It was deliberate. Everyone saw it.
Regulus's wand vanished back into his sleeve. He placed his left hand on the table, lowered his head, and continued writing. The quill scratched steadily against the parchment. *Scritch-scratch.*
It was as if nothing had happened.
The silence lasted for ten full seconds.
James Potter stood frozen, his wand still raised, looking like a statue of a duelist. His eyes were wide, reflecting the empty air where his spell used to be.
"You..." James's voice cracked. He swallowed hard. "What did you do?"
Regulus didn't answer. He didn't even look up.
James clenched his fists. His face flushed with a mix of fury and confusion. He wanted to shout, to demand an answer, but the sheer disregard was suffocating him.
He wasn't stupid. James Potter was arrogant and reckless, but he paid attention in class.
He knew what this was. The appendix of *The Standard Book of Spells, Grade 1* mentioned it as a theoretical concept: *Magical Interference.* The ability for a sufficiently powerful wizard to dismantle the structure of a spell mid-air using raw will and superior control.
It was theoretical because first-years didn't do it. Most adult wizards didn't do it.
But Regulus Black just sat there, dismantling magic as if he were swatting a fly.
"What kind of spell was that?" Remus whispered, stepping slightly in front of James, as if to shield him.
"It wasn't a spell," Sirius said. His voice was flat. He stepped into the compartment, standing shoulder-to-shoulder with James, but his eyes were fixed on Regulus.
Sirius's mind was racing. He knew Regulus was studious, but this? This was mastery. It was terrifying.
"What do you mean?" James snapped, turning to his friend.
"It means you can't beat him," Sirius said calmly. He didn't want to sound like he was taking sides, but he had to be honest. "We can't beat him. Not right now. So leave it."
James opened his mouth to argue, his pride stinging. But he looked at the spot where his spell had vanished, then at the boy writing in the notebook.
He lowered his wand.
Regulus finally looked up at Sirius. He gave a single, almost imperceptible nod. Then he returned to his work.
The Marauders retreated. James cast one last baffled look over his shoulder before the door slid shut.
In the corridor, Lily Evans and Severus Snape remained.
Lily had let go of Snape's arm, but she hadn't moved. Her green eyes were wide. Snape was staring at Regulus with a look of intense, guarded wariness.
"Are you alright?" Lily asked, her voice breaking the silence.
Regulus looked up. He set his quill down.
"Thank you for asking," he said politely. "Though strictly speaking, Mr. Snape is the one who should be thanked. The spell was intended for him."
Lily blinked, taken aback by his manner. "No... I mean, it's nothing."
Snape's lips twitched. He ignored the pleasantries. "How did you do that?"
Regulus stood up. He smoothed his robes.
"Before we discuss mechanics, perhaps introductions are in order. I am Regulus Black."
"Black?" Lily's eyes widened. "You're... Sirius Black's brother?"
Regulus gave a stiff nod.
"I am Lily Evans," she said, recovering her manners. "Second year, Gryffindor. And this is Severus Snape. Slytherin."
Snape nodded curtly, his posture rigid.
"I know your names," Regulus said.
Lily blinked. "You do?"
"Professor Slughorn mentioned you," Regulus lied smoothly—or rather, used future knowledge as current fact. "He said Hogwarts has two second-years with exceptional talent in Potions. He suggested I seek you out."
Lily's face flushed pink. Her eyes lit up. "Really? He said that?"
Snape's reaction was more complex. His chin lifted slightly, pride warring with suspicion. He was used to hearing "talented," but usually it was followed by a sneer about his poverty or his blood.
"So you know who we are," Snape said, his voice raspy. "But what we just saw... that is not first-year magic, Mr. Black."
Regulus studied him. *Severus Snape. Sensitive. Insecure. Brilliant.*
"The principles of spell analysis and interference are not complicated," Regulus said. "But they require a high degree of precision."
"How high?" Snape pressed.
*Impolite,* Regulus noted. *But valuable.*
"Higher than most adult wizards possess," Regulus admitted calmly. "I have practiced for a long time."
"How old were you when you started?" Lily asked, curiosity overcoming her shock.
"As far back as I can remember," Regulus said. "There is a library in my house."
It was a partial truth. Books didn't teach this kind of control. But Lily, coming from a Muggle family, wouldn't know the difference.
She nodded, impressed. "So you're... the kind of person who likes to learn."
"Learning is necessary," Regulus agreed. "For a wizard, knowledge is power."
*Especially knowledge about Muggles,* he added silently.
Snape raised an eyebrow. The suspicion in his eyes receded slightly, replaced by a grudging respect. A fellow scholar.
"So," Snape asked, "which House do you plan to join?"
"Slytherin," Regulus said without hesitation. "It is family tradition."
Lily's smile dimmed. She looked at Snape, then at Regulus. "Slytherin... is fine. Severus is there."
*But there are people there who hate me,* her eyes said.
Regulus understood. "Every House has people worth learning from," he said diplomatically. "And people not worth wasting time on."
Lily smiled again, grateful for the nuance. "You're right. Well... see you at the Sorting?"
"See you."
Lily tugged at Snape's sleeve. "We should go, Severus."
Snape gave Regulus one last, calculating look. He nodded, then turned to follow her.
Regulus sat back down. The carriage was quiet again.
He picked up his quill.
*Phase one complete,* he thought. *The Lions are warned. The Snakes are interested.*