SYSTEM NOTIFICATION: You are reading [Threshold Walker: The Silver Circuit]
Rain fell in gray sheets across Seoul, turning the evening streets into a blur of neon reflections. Jin stared through the taxi window at the gleaming buildings of the university research district, his grip tightening on the worn sketchbook in his lap. Next to him, Jin-Ah clutched her own notebook, its pages filled with mathematical formulas Jin had only begun to understand.
The visit to their family apartment had been unexpectedly emotional. Walking through rooms untouched for months, past photographs of happier times, Jin had felt the full weight of how much their lives had changed. They'd found Jin-Ah's research notebook exactly where she'd left it, carefully hidden beneath a loose floorboard in her bedroom. Jin's childhood sketchbook had been more difficult to locate—eventually discovered in a storage box in their mother's closet.
When Jin had opened it, his breath caught. Page after page of intricate silver patterns, drawn by a child's unsteady hand. Patterns he now recognized as threshold energy pathways. He'd been seeing them even then, years before the First Breach.
"The rain should help," Dr. Ha said from the front passenger seat, interrupting Jin's thoughts. "Division detection equipment is less effective in severe weather."
Tae-Woo, who was driving, nodded. "The university security feeds show minimal activity in the research wing. Most staff left early due to the storm warnings."
Jin met Jin-Ah's eyes. The tension in her posture mirrored his own. After spending the day examining their recovered notebooks, they'd discovered something extraordinary—Jin's childhood drawings and Jin-Ah's mathematical formulas formed complementary patterns. When overlaid, they created a complete circuit diagram more detailed than anything they'd seen before.
The diagram had confirmed what their mother told them about their father splitting the knowledge between his children. Jin possessed the intuitive understanding of threshold pathways, while Jin-Ah held the mathematical framework needed to stabilize them.
"We're approaching the drop point," Tae-Woo announced, pulling the taxi to the curb three blocks from their destination. "Remember, I can only maintain the electronic interference for fifteen minutes. After that, their systems will reset."
Dr. Ha checked her tablet one last time. "According to the Network's intelligence, the fifth floor east wing is where they've preserved your father's research space. The Division converted surrounding areas to monitoring stations, but they've kept his office largely intact for study purposes."
Jin slipped the silver disk Agent Song had given him into his pocket. "And you're sure this will work?"
"No," Dr. Ha admitted. "But Agent Song took a significant risk giving it to you. If your father truly trusted her, there's a reasonable chance it's legitimate."
Jin and Dr. Ha would enter the building while Jin-Ah remained with Tae-Woo in the taxi, coordinating their movements and monitoring Division communications. Jin-Ah had argued fiercely to come along, but ultimately recognized that her threshold abilities weren't developed enough for such a high-risk operation.
"Stay in contact," Jin-Ah said, squeezing her brother's hand. "And be careful with that disk. If it really does access Dad's private archives..."
"We'll get what we can and get out," Jin promised. "No heroics."
Fifteen minutes later, Jin and Dr. Ha stood in the service entrance of the Theoretical Physics Research Building, rain dripping from their coats. Tae-Woo's electronic interference had disabled the security system just long enough for them to slip inside undetected.
Jin extended his perception, silver lines blooming across his vision as he searched for signs of security personnel or threshold monitoring equipment. The building felt strangely quiet, most of the silver pathways dormant or flowing sluggishly.
"Third floor security station is empty," Jin reported, pointing to the emergency stairwell. "But there's something odd about the fifth floor. The silver lines there are... distorted."
"Division dampening technology," Dr. Ha suggested. "They've been developing ways to suppress threshold energy in controlled environments."
They moved swiftly through the building, Jin's enhanced perception guiding them around potential encounters with the handful of researchers still working late. When they reached the fourth floor, Jin paused, a familiar sensation prickling at his awareness.
"Wait," he whispered, raising a hand. "I've felt this before. At the Transit Point."
Dr. Ha looked at him sharply. "What is it?"
"Threshold memory," Jin said, extending his awareness. "This place holds echoes, like the convergence points do."
The stairwell around them seemed to shimmer, reality thinning as Jin focused on the sensation. For a brief moment, he glimpsed a shadow moving up the stairs ahead of them—a tall figure in a lab coat, carrying a stack of folders.
"My father," Jin breathed. "He's showing me the way."
The echo disappeared as quickly as it had appeared, but Jin felt a renewed sense of certainty. They were on the right path.
The fifth floor was noticeably different from the floors below. Modern security doors had been installed, and Jin could see faint outlines of monitoring equipment positioned at strategic intervals. Most concerning was the strange deadening effect that seemed to permeate the air—like the silver lines were being actively suppressed.
"Division security clearance required beyond this point," Dr. Ha read from the electronic panel beside the main door.
Jin examined the panel, noting a small circular indentation beside the standard card reader. Without hesitation, he removed the silver disk from his pocket and pressed it into the indentation.
For a moment, nothing happened. Then the panel emitted a soft chime, displaying a message: "SECONDARY PROTOCOL INITIATED. WELCOME, DR. SEO."
"That's... unexpected," Dr. Ha said as the doors slid open. "Your father built a backdoor into the security system."
"Or Agent Song added one," Jin suggested, though he couldn't quite believe someone would have that level of access without being detected.
They entered a corridor lined with modern research equipment—threshold detection arrays, energy containment units, and data terminals displaying complex readings. Unlike the rest of the building, this area hummed with activity despite the absence of personnel. Machines collected and processed data automatically, monitoring something Jin couldn't immediately identify.
At the end of the corridor stood an ordinary wooden door with a simple nameplate: "Dr. Seo Jin-Woo, Theoretical Physics."
"It's exactly as I remember it," Jin said softly, memories of childhood visits flooding back. "He never wanted a fancy office, even after he became department chair."
The silver disk unlocked this door as well, revealing a space frozen in time. Books and papers remained exactly where Dr. Seo had left them five years ago. His coffee mug still sat on the desk, long emptied but never removed. The only additions were discreet monitoring devices positioned around the room, their lights blinking steadily.
Jin felt a tightness in his throat as he moved through the space, touching the familiar desk where he'd once sat drawing while his father worked on complex equations nearby.
"They've preserved it like a museum exhibit," Dr. Ha observed, examining the monitors. "They're recording threshold energy fluctuations 24/7."
Jin was barely listening. His attention had fixed on something he'd never noticed during his childhood visits—a faint silver line tracing the edge of his father's desk, visible only to threshold-sensitive perception.
Following instinct, Jin placed his palm flat against the wooden surface. The silver line brightened immediately, spreading outward to form a complex geometric pattern across the desk's surface.
"Ha Ji-Ah," Jin said, not looking up. "Can you disable those monitoring devices?"
Dr. Ha glanced at him, then at the pattern forming beneath his hand. Without a word, she moved to the nearest monitor and began working on its control panel.
"I'm rerouting the data stream to play the last six hours on a loop," she explained. "They'll notice eventually, but it should buy us some time."
As the last monitor's light shifted from green to amber, Jin focused on the pattern spread across the desk. It matched one of the drawings from his childhood sketchbook—a series of interlocking silver circles surrounding a central star.
"This is it," he said. "The Origin Point. It's not just in this room; it's built into the desk itself."
Jin reached for the silver disk again, guided by an intuition he couldn't explain. At the center of the pattern was a small knot in the wood that had always fascinated him as a child. He pressed the disk against this spot, feeling a faint vibration as the two connected.
The desk's surface seemed to ripple, and a hidden compartment slid open beneath the main drawer. Inside lay a slim metallic case and a handwritten envelope with Jin's name.
With trembling fingers, Jin removed both items. He handed the case to Dr. Ha while opening the envelope.
"It's dated two days before he disappeared," Jin said, scanning the letter. "He knew something was going to happen."
Jin,
If you're reading this, then my contingencies have activated, which means I've been gone for some time. I hope it has not been too long, for all our sakes.
The fifth point you've discovered is where everything began—the Origin. It is the seed from which the entire circuit grew, and it contains the baseline pattern for all other points. What you need to know cannot be written, only experienced. Trust your abilities and your sister's calculations.
Remember: the circuit is a rescue system, but it's also a safeguard. Some doors should remain locked.
The silver disk contains the true circuit map and my research journals. The access protocols for the remaining points are encoded within. Jin-Ah will understand the mathematical key needed to decode them.
Watch for the echo. It will guide you when I cannot.
With love and faith,Your father
Jin looked up from the letter, emotions threatening to overwhelm him. "He knew this would happen. All of it."
Dr. Ha was examining the case, which had opened to reveal a specialized data storage device. "This technology... it's far beyond what was available five years ago. Some of these components shouldn't even exist yet."
A soft chime from their comms interrupted them—Tae-Woo's warning that they had five minutes remaining before the interference failed.
Jin turned his attention back to the desk, to the convergence point hidden within it. Unlike the other points he'd encountered, this one felt... fundamental. As if it were the source pattern from which all others derived.
"I need to activate it," Jin said, placing both hands on the pattern. "The letter says there's information that can only be experienced."
Dr. Ha looked concerned. "Jin, the Division will detect a significant threshold event, interference or not. It could trigger an immediate response."
"We don't have a choice," Jin replied, already feeling the energy building beneath his palms. "My father left something here for me to find."
He closed his eyes, focusing on the silver lines that formed the Origin Point pattern. Unlike previous points that required him to simply make contact, this one seemed to be waiting for something more specific.
Jin thought of the overlapping patterns from his and Jin-Ah's notebooks. On impulse, he activated their communication link.
"Jin-Ah," he said. "I need your help."
His sister's voice came through immediately. "What's happening? Your threshold signature just spiked on Tae-Woo's monitor."
"The Origin Point is here, but it needs both keys to activate," Jin explained. "I need you to recite the primary stabilization equation. The one on page seventeen of your notebook."
There was a moment of hesitation before Jin-Ah began speaking, her voice precise as she recited a complex mathematical formula. As the numbers and symbols flowed through the communication link, Jin visualized them overlaying the pattern beneath his hands.
The effect was immediate. The silver lines brightened dramatically, the pattern expanding beyond the desk to encompass the entire room. Jin felt the familiar resonance of a convergence point activating, but with an intensity that surpassed all previous experiences.
SYSTEM NOTIFICATION: Convergence Point 5 (Origin) has been activated!
The silver lines pulsed once, twice, then stabilized into a steady glow. The room itself seemed to shimmer, reality thinning as the boundary between worlds weakened.
And then Jin saw him.
Standing on the other side of the desk was the translucent figure of Dr. Seo Jin-Woo—not as Jin had last seen him five years ago, but as he might appear now. His father's face showed new lines of care, and his hair had silvered at the temples. He wore what appeared to be a researcher's uniform unlike any Jin had seen before, with strange geometric patterns embroidered along the cuffs.
"Dad?" Jin whispered, his voice barely audible.
The figure smiled, raising a hand in greeting. His lips moved, but no sound emerged in the physical world. Instead, Jin felt the words forming directly in his mind.
Jin. You found it. I knew you would.
"Is it really you?" Jin asked, desperately wanting to reach across the desk, but afraid the apparition would vanish if he moved.
An echo, but connected to me. I don't have much time. The figure gestured to the case and the pattern still glowing on the desk. The Origin contains the truth about the Threshold. It's not what the Division believes it to be.
"Where are you?" Jin pressed. "How can we find you?"
The Between-Space. A stable pocket within the Threshold. I've been continuing my research. Dr. Seo's expression grew serious. Jin, listen carefully. The Division isn't the only group searching for the circuit points. There's another faction, one that emerged from within the Threshold itself.
"Threshold entities?" Dr. Ha asked, having moved to stand beside Jin.
The figure nodded, acknowledging her presence. Hello, Ji-Ah. Still watching over my son, I see. He turned back to Jin. Not just entities. Humans who've been changed by extended Threshold exposure. They call themselves the Evolved. They believe the Threshold is the next stage of human development and seek to merge our realities permanently.
Jin felt a chill. "Is that possible?"
With a completed circuit, yes. That's why I built in safeguards—the split keys, the sequential activation requirements. Dr. Seo's image flickered briefly. Our connection is weakening. Jin, you must find and secure all convergence points before the Evolved or the Division can use them. The full circuit has tremendous power, but terrible risk if misused.
"How do we find you?" Jin asked again, desperate as he sensed the connection fading.
Complete the circuit. All seventeen points. The final two— The image stuttered, breaking apart momentarily before reforming. —hidden for protection. Coordinates in the case. Jin-Ah will understand.
Dr. Seo looked over Jin's shoulder suddenly, as if sensing something beyond Jin's perception. They're coming. Both Division and Evolved agents. Trust Song, but be careful—her loyalty is divided. He turned back to Jin, his expression softening. Tell your mother I'm coming home. Tell Jin-Ah—
The image dissolved into silver particles as a shrill alarm suddenly blared throughout the building. The Origin Point's glow dimmed but remained active, pulsing in rhythm with Jin's heartbeat.
"Division breach protocols activated," an automated voice announced through the building's speakers. "Unknown threshold event detected. Security response teams deployed."
Jin stood frozen, staring at the space where his father had been. Dr. Ha grabbed his arm urgently.
"Jin, we need to move. Now."
He nodded numbly, gathering the case and letter and shoving them into his backpack. The silver disk was now fused to the desk's surface, incorporated into the Origin Point's permanent structure.
"Tae-Woo says Division response teams are three minutes out," Dr. Ha reported, checking her comm. "We need an alternate exit."
Jin forced himself to focus, extending his perception beyond the office. The silver lines throughout the building had intensified with the Origin Point's activation, making the pathways clearer than ever before.
"There," he said, pointing to a maintenance corridor not visible on the standard building plans. "The silver lines are showing a path to the east stairwell. It bypasses the main security checkpoints."
They moved quickly, Jin leading the way through a series of service passages that seemed to shift and reveal themselves just as they needed them. It was as if the Origin Point was actively helping them escape, manipulating the threshold energy to create safe pathways.
As they descended through the east stairwell, Jin felt a sudden surge of threshold energy from below—different from the Division's signature, wilder and less controlled.
"Stop," he whispered, pulling Dr. Ha back. "Someone's coming up. And it's not Division."
Through his enhanced perception, Jin could see a figure ascending the stairs two floors below them—surrounded not by the ordered silver lines he was accustomed to, but by swirling, chaotic patterns that seemed to bend reality around them.
"Evolved," he said, remembering his father's warning.
Dr. Ha tensed. "How do you know?"
"The threshold energy pattern. It's... wrong somehow. Unstable." Jin concentrated, searching for an alternative route. "This way."
He led them through a door onto the third floor, navigating by the silver pathways that seemed increasingly responsive to his will. They moved through darkened laboratories and empty classrooms, staying ahead of both the Division teams entering from the ground floor and the unknown Evolved agent ascending from below.
Jin's communicator vibrated. "Jin," Jin-Ah's voice came through, tense with concern. "Division's locked down the entire building. They've got teams at every marked exit."
"We're not using a marked exit," Jin replied, following a particularly bright silver line that led toward the building's eastern exterior. "Tell Tae-Woo to bring the car to the east loading dock service road."
The silver line led them to a maintenance room housing climate control equipment. Jin examined the wall where the line disappeared, finding a subtle seam that suggested a service access panel.
"Here," he said, running his fingers along the edge. "There should be a way through."
Dr. Ha helped him locate the release mechanism, revealing a narrow passage used for accessing exterior HVAC units. It was tight, but navigable, and most importantly, not on any building schematics that would be available to the Division.
They emerged onto a narrow maintenance platform three stories above the loading dock area. Rain continued to pour, reducing visibility and, hopefully, their chances of being spotted.
"Now what?" Dr. Ha asked, looking at the substantial drop below them.
Jin examined the silver lines extending downward, forming a complex net that seemed almost ladder-like in structure.
"I think..." he began, then stopped, uncertain how to explain the intuition forming in his mind.
"What are you seeing?" Dr. Ha pressed.
"The threshold energy. It's creating a path." Jin hesitated. "But using it would require more active manipulation than anything I've done before."
Before Dr. Ha could respond, the maintenance door behind them burst open. A figure stepped onto the platform—a woman in civilian clothes, but with eyes that glowed an unnatural silver-blue. Unlike Jin's silver eyes, which appeared during ability use, hers seemed permanently transformed.
"The son of Seo Jin-Woo," she said, her voice carrying an odd harmonic quality. "We've been waiting for you to find the Origin."
Jin positioned himself between the woman and Dr. Ha. "Who are you?"
"Someone who's seen the truth of the Threshold." She extended a hand, silver-blue energy coiling around her fingers. "Your father's work doesn't need to be completed. It needs to be transcended. Come with me, and I'll show you what the Threshold truly offers."
Jin felt the woman's power pushing against his awareness—familiar threshold energy, but twisted somehow, overcharged and unstable.
"You're Evolved," he said, remembering his father's warning.
The woman smiled. "We want to elevate humanity. Your father understands this now. Why do you think he remains in the Between-Space? He's beginning the transformation himself."
"You're lying," Jin said, anger flaring. "My father is trying to find a way home."
"Home is a concept that will soon be meaningless," the woman replied, taking a step closer. Behind her, Jin could see more figures approaching through the maintenance door. "Reality is malleable. The Threshold teaches us this. Join us willingly, and you'll understand."
Jin glanced behind him at the silver pathway extending downward, then at Dr. Ha. A plan formed in his mind—risky, but possibly their only option.
"Now!" he shouted, grabbing Dr. Ha's arm and pulling her toward the edge of the platform.
As they fell, Jin focused every ounce of his concentration on the silver lines below them. His hands extended, threshold energy flowing from his fingertips as he attempted to solidify the pattern he'd seen.
SYSTEM NOTIFICATION: Ability [Line Manipulation Level 2] has evolved!
The silver lines coalesced, forming a spiraling slide that caught them mid-fall, guiding their descent at a controllable speed. Jin felt the strain immediately—blood running from his nose, vision blurring at the edges—but he maintained his focus until they reached the ground safely.
Dr. Ha steadied him as his knees buckled. "That was... unexpected."
"Line Tracing evolution," Jin managed, wiping blood from his face. "Dad's presence at the Origin Point must have accelerated my abilities."
A sleek black car pulled up beside them, its engine almost silent. The window lowered to reveal Tae-Woo's concerned face.
"In. Now," he ordered. "Division's converging from all directions."
They scrambled into the backseat, where Jin-Ah immediately grabbed her brother's shoulders, examining him with wide, frightened eyes.
"You're bleeding again," she said, pressing a cloth to his nose. "What happened up there? Your threshold signature went crazy on Tae-Woo's monitor."
"I saw Dad," Jin said, his voice hoarse with emotion and exhaustion. "And we were pursued by something else. Not Division. Someone called Evolved."
Jin-Ah's expression shifted from concern to concentration as Tae-Woo accelerated away from the research building, navigating through back roads to avoid Division checkpoints.
"Tell me everything," she said, already reaching for her notebook.
As they drove through the rainy night, Jin recounted the encounter with their father and the warning about the Evolved faction. Dr. Ha examined the case they'd recovered, which contained data storage devices of unusual design and what appeared to be a complete map of all seventeen convergence points—including the two final locations that had never been physically established.
"The Dongdaemun area and the Han River confluence," Dr. Ha noted, studying the map. "Those must be the last two points your father mentioned."
Jin nodded, struggling to process everything they'd learned. The Origin Point was now active, permanently linking to the network they'd briefly connected to in Chapter 5. But his father's warning about the circuit's dual nature—both rescue system and safeguard—raised troubling questions.
"Dad said the circuit could be used to merge realities if misused," Jin said, meeting Jin-Ah's eyes. "That's why he split the keys between us."
"The genetic key and the mathematical key," Jin-Ah murmured, paging through her notebook. "Together they form a complete activation and stabilization protocol."
Jin leaned back, sudden exhaustion washing over him as the adrenaline faded. "He's alive, Jin-Ah. Really alive. And he's coming home."
Jin-Ah squeezed his hand, her eyes bright with unshed tears. "We'll find a way. Together."
As the car disappeared into the storm-washed streets of Seoul, Jin glanced at the case containing his father's research. Whatever threats lay ahead—Division, Evolved, or something yet unknown—they finally had a clear purpose. Complete the circuit. Find their father. Bring him home.
But the woman's words lingered in his mind, raising doubt like a persistent shadow: Why do you think he remains in the Between-Space? He's beginning the transformation himself.
Was his father truly working to return home? Or had five years in the Threshold changed him in ways they couldn't yet understand?
The answers, Jin suspected, lay in the remaining convergence points—and the increasingly dangerous path to activate them.
Author's Note: Jin has finally seen his father and confirmed he's alive in the Threshold! But this new "Evolved" faction introduces another layer of danger. What do you think—can Jin trust the vision of his father, or might the Evolved woman be telling the truth about Dr. Seo's transformation? And what does Agent Song's "divided loyalty" mean for our heroes? Share your theories in the comments!
Coming Next: Chapter 8: Echo Memories - An entity from the Origin Point follows Jin, claiming to have information about Dr. Seo's final days before entering the Threshold. Meanwhile, Division forces close in on the Network's safe house, forcing a dangerous evacuation.