"It would appeal to his sense of irony and his connection to the school," Marquas explained, navigating the delicate balance between informed speculation and revealing his foreknowledge. "Plus, there's the Room of Requirement, a chamber that can transform itself based on the seeker's needs, including becoming the perfect hiding place. Like keeping your embarrassing teenage poetry journal in the school library, nobody would think to look there because it's too obvious."
"Speaking from personal experience?" Regulus chuckled, his gray eyes momentarily brightening with amusement before returning to the serious matter at hand. "If there is a Horcrux at Hogwarts, where specifically would he hide it?"
"Based on my analysis of Voldemort's psychology," Marquas said, catching himself before mentioning the books, "somewhere significant to him personally, connected to the founders if possible. The Room of Requirement seems the most logical location, specifically in its storage room configuration."
"The what room?" Regulus looked confused, his brow furrowing as he leaned forward in his chair.
"Ah, right," Marquas realized this wasn't common knowledge. "The Come and Go Room," he explained, watching recognition flicker in Regulus' eyes. "Hidden on the seventh floor behind a tapestry of Barnabas the Barmy. Walk past it three times focusing on what you need, and the castle responds... quite ingeniously. One of its forms is essentially a vast storage room where objects have been hidden for centuries."
"How do you know about this?" Regulus asked suspiciously, his fingers tightening around his glass of firewhisky, the amber liquid catching the dim light.
"I was a Hogwarts student too, you know," Marquas replied smoothly, "Some of us spent our school years exploring the castle rather than practicing family-approved sneering techniques in the mirror."
Regulus looked offended for a moment before a reluctant smile tugged at his lips. "Fair enough. I did spend an inordinate amount of time perfecting the proper aristocratic disdain." His expression softened with the memory. "Mother insisted it was as important as table manners." He swirled the remaining firewhisky in his glass, watching the golden liquid coat the sides. "I've heard rumors of such a room, though I never found it myself during my time at Hogwarts."
"It exists," Marquas confirmed. "And given your official 'deceased' status, smuggling you into Hogwarts for an investigation presents certain logistical challenges, but nothing insurmountable with proper planning."
The fire crackled in the hearth as they spent the next several hours developing dual strategies: Marquas's approach to the Death Eater investigation and their joint plan for searching Hogwarts for the diadem Horcrux. The air grew heavy with pipe smoke and the sharp tang of firewhisky as diagrams were drawn and contingencies mapped. By the time they concluded, it was well past midnight, the bottle considerably emptier than when they'd started, and a comfortable warmth had settled over the room despite the winter chill seeping through the ancient windowpanes.
"One thing I don't understand," Regulus said as they prepared to depart, shrugging into his heavy traveling cloak. "If you're going to frame Avery anyway, why bother with a genuine investigation? Why not just fabricate everything?"
"Because Voldemort isn't stupid," Marquas explained, summoning his own cloak from a hook across the room. "He'll verify any evidence I present. The security weaknesses need to be real, the operational failures accurately documented. I'll identify how information is leaking, perhaps through poorly secured meeting locations or indiscreet conversations in public venues, while directing suspicion toward Avery's known associates. Only the final conclusion, who exploited those weaknesses, contains the deception."
"Elegant," Regulus acknowledged, a newfound respect evident in his voice. "A lie wrapped in layers of truth is always more convincing."
"A principle that applies to espionage and teaching teenagers equally well," Marquas observed dryly. "Speaking of which, I should return to Hogwarts before my absence raises questions."
As he prepared to Apparate, Regulus hesitated, uncharacteristic vulnerability crossing his aristocratic features. "Do you ever wonder if we're actually making a difference? Or just delaying the inevitable?"
Marquas paused, studying the younger man whose haunted eyes revealed the burden of his choices. "I believe we're rewriting the story," he said finally, choosing his words with care. "The original ending was tragic for too many people, yourself included. Every change we make creates possibilities that didn't exist before. The path may be uncertain, but it's one worth taking."
"Rewriting the story," Regulus repeated, the phrase settling over him like a comforting cloak but he didn't understand the meaning behind it. His shoulders straightened slightly. "I like that framing. It gives purpose to all this risk."
••••
Marquas Apparated to the edge of Hogwarts grounds, the sharp report of his arrival startling a nearby thestral into flight. The creature's leathery wings beat against the night air as he began the long walk up to the castle, using the solitary journey to shift mentally from conspirator back to professor. The crunch of frozen grass beneath his boots and the distant hooting of owls from the forest accompanied his thoughts as they turned to practical matters, lesson plans, grading, and maintaining his precarious balancing act. By the time the castle's great doors came into view, illuminated by moonlight against the dark stone, he had carefully tucked away Regulus' information into the compartmentalized sections of his mind where he stored his most dangerous secrets.
Back in his quarters, he wrote:
Day 110: Voldemort suspects a traitor in his ranks. Ironic development: I've been tasked with identifying this traitor, myself. Beginning thorough inquiry while preparing to redirect suspicion toward Avery. Morally questionable but strategically necessary. Horcrux detection spell progressing. Planning Hogwarts search for diadem with R.A.B. He continues objecting to organization name despite obvious accuracy of descriptor.
He closed the journal with a sigh that seemed to come from deep within, the weight of his increasingly complex deception heavy on his mind. The coming weeks would test his abilities as never before, conducting a counter-intelligence operation while maintaining his cover as a loyal Death Eater, continuing to teach effectively, advancing their Horcrux hunt, and overseeing the rapid expansion of S. Prince Labs.
Running his fingers through his hair, Marquas poured a small measure of firewhisky into a crystal glass, not for the intoxication but for the grounding effect of the burn. He stood before the fire, watching the flames dance and cast shifting shadows across the stone walls. Despite the exhaustion that settled into his bones, there was an undeniable clarity that came with having chosen this path. The software developer he had once been would never have imagined standing here, a key player in a magical war, making decisions that could alter the course of history.
As the last of the whisky warmed his throat, a soft chime resonated from his wand, alerting him to someone approaching his quarters. But this time, he didn't bother drawing his wand, his dungeon-like cave had become far too frequented lately, even attracting some of the most powerful wizards in hogwards. He moved silently to the door, the plush carpet muffling his footsteps as he cast a discreet revealing spell to identify the visitor.
The magical signature was unmistakable, Albus Dumbledore stood outside, his magical aura distinctive even through the heavy oak door. More concerning was the unusual tension Marquas could sense in that aura, suggesting urgency.
Marquas opened the door immediately, schooling his features into the composed mask of Severus Snape. "Headmaster? What's happened?"
"I apologize for the late hour, Severus," Dumbledore said quietly, the usual twinkle in his blue eyes dimmed by concern. The scent of lemon and something indefinably ancient accompanied him as he entered. "But I've just received troubling news that concerns us both. May I come in?"
Stepping aside, Marquas admitted the elderly wizard, quickly casting additional privacy charms around his quarters. The subtle shimmer of protective magic settled over the room like a fine mist before fading from view. "What news?"
Dumbledore settled into a chair, his normally immaculate robes slightly rumpled, a tell-tale sign of a long evening. The firelight cast deep shadows beneath his eyes as he stroked his silver beard thoughtfully. "I've received intelligence that Voldemort has initiated an internal investigation into possible treachery among his followers. Given your position, this places you in considerable danger."
"Actually," Marquas replied with grim humor, offering the Headmaster a cup of tea from the service that appeared with a snap of his fingers, "I've been assigned to conduct that investigation myself."
Dumbledore's eyebrows rose in surprise, his hand pausing midway to accepting the tea. "Indeed? That is... unexpected."
"Apparently, my 'analytical skills' and relative distance from daily operations make me ideal for the task," Marquas explained, unable to keep a hint of irony from his voice as he took the opposite chair. "Voldemort wants me to identify weaknesses in their security protocols and determine who might be exploiting them."
"Fascinating," Dumbledore murmured, "This could be either an extraordinary opportunity or a carefully laid trap."
"My assessment exactly," Marquas nodded, "I intend to proceed with caution, providing real insights into their operational vulnerabilities while misdirecting attention away from my own activities."
"A delicate balance," Dumbledore acknowledged, his eyes studying Marquas with that penetrating gaze that always seemed to see more than was comfortable. "Is there anything I can do to assist?"
Marquas considered the offer carefully, weighing vulnerabilities against advantages. "Actually, yes. I need believable intelligence to feed Voldemort, information that appears valuable but won't actually endanger Order operations. Controlled leaks that will reinforce my cover without causing real damage."
Dumbledore nodded slowly, his long fingers steepled before him. "I can arrange that. Authentic but outdated information, perhaps, or details of operations that exist only on paper."
"Exactly," Marquas confirmed. "And in return, I'll have unprecedented access to Death Eater personnel files and operational procedures, intelligence that could prove invaluable to the Order."
They discussed the parameters of this arrangement for some time, the clock on the mantle marking the deepening night with soft chimes, with Dumbledore eventually agreeing to provide carefully curated intelligence that Marquas could "discover" during his investigation. It was a dangerous game they were playing, but one with potentially enormous benefits if executed correctly.
As Dumbledore prepared to leave, he paused at the door, his hand resting on the ancient wood. The momentary hesitation was so uncharacteristic of the normally decisive Headmaster that Marquas found himself instantly alert.
"Severus," Dumbledore said, his voice softer than usual, "I feel compelled to ask, are you certain you wish to continue in this role? The risks increase exponentially with each passing month. No one would think less of you if you chose to step back to a position of lesser danger."
The question caught Marquas off guard. Canon Snape had never been given a choice, his path of atonement allowed no exit ramps. That Dumbledore would even offer the possibility of withdrawal suggested a fundamental shift in their relationship, a respect that had never existed in the original timeline where Snape was viewed as a tool of penance rather than a valued ally.
"I'm certain," Marquas replied after a moment's reflection, meeting the older wizard's gaze steadily. "This is where I can make the greatest difference. Besides," he added with the faintest hint of a smile, "I've always had a knack for impossible situations."
Dumbledore studied him with those penetrating blue eyes that seemed to contain galaxies of knowledge. "You continue to surprise me, Severus.
Damn it, did I just sell myself out again? Foolish. This old man's getting harder to fool by the day, Marquas thought bitterly. Whenever Dumbledore said, 'You've surprised me,' it was never a compliment. It meant he'd seen through something, and that was deeply unsettling.
After the Headmaster departed, the lingering scent of lemon drops and aged parchment slowly fading, Marquas stood for a long time at his window, gazing out over the moonlit grounds of Hogwarts. Snowflakes drifted past the frosted glass, each crystal catching moonlight before joining its brethren on the grounds below. He pressed his palm against the cold window, watching his breath fog the glass as an owl swooped silently across the lake, its reflection rippling in the dark water.
The stakes were rising, the game becoming increasingly dangerous. One misstep in his complex performance could mean disaster not just for himself, but for everything they were working toward. Yet despite the danger, or perhaps because of it, he felt a strange clarity of purpose that had eluded him in his previous life.
"Deception within deception," he murmured to his reflection in the window glass, his voice barely audible even to himself. "Let's see how you handle this plot twist, Tom."
Outside, the snow transformed Hogwarts into something deceptively serene, much like his carefully constructed persona, beautiful on the surface while concealing dangerous secrets beneath. He turned away from the window, mind already calculating his next moves in this deadly chess match where the pieces were people and the stakes were measured in lives.