Taeyoung sent the perimeter log at eleven-forty.
It came through the tributary relay in two packets — the scene access records from the first twenty-four hours after the massacre, sixty-three individual entries, names and credentials and timestamps and the specific notation system the Association used for crime scene integrity documentation. Jisoo received both packets with her palms on the floor and decoded them onto Mirae's tablet in thirty minutes.
Sixty-three entries. Official first responders. Two senior investigators. Forensic specialists. The Association's press liaison who'd been on-site to manage the media perimeter. Medical examiner's team.
And three entries in the first-response window that Taeyoung had flagged — logged before the official investigation team arrived, before the medical examiner, before even the first uniformed officers' incident report timestamp.
The third of those entries: a practitioner listed under a provisional practitioner registry number rather than a full Association license. Not unusual — provisional status covered awakened individuals in the early stages of the registration process, before full licensing cleared. An Association liaison had apparently vouched for the entry.
The vouching liaison: Bae Sunghoon's administrative office.
The name attached to the provisional registry number: Na Minjun.
"Na Minjun," Seonghwa said.
Hyunwoo looked at the name for a long time. "Provisional registry. Bae's office vouched it. The number traces to a registration application filed six months before the massacre that was still pending review at the time of the scene entry." He pulled out his phone. "That's not unusual — applications take eight to twelve months. What's unusual is that a pending-review practitioner got waved through a crime scene perimeter by the director's administrative office."
"They needed someone there who could read blood-will evidence before the forensics team could document what it actually showed," Seonghwa said. "Before the investigation had a record of the original state."
"Na Minjun went in, altered the blood evidence, placed the planted samples, and left." Hyunwoo looked at the log. "The official forensics team arrived after. The scene they documented was already altered."
"The registration application," Mirae said. She was reading over his shoulder. "Provisional numbers are tied to personal identification. If the application exists in the Association database—"
"Taeyoung's looking." Hyunwoo sent the message before she finished. "Give him an hour. The provisional registry goes back four years — he'll need to cross-reference the file through a system that isn't on Bae's office's monitoring list."
Jisoo had her palms on the floor. "Na Minjun," she said.
Something in the way she said it.
"You recognize it," Seonghwa said.
"Not the name. The frequency structure." She kept reading. "The frequency signature that Goh transmitted — the mole's blood-will profile. I've been running it through my read archive for two days, the way the old way practitioner's read-memory works, the continuous low-level comparison that happens when a specific frequency is flagged for identification." She paused. "The mole's signature has the conflict pattern I described. Extended internal pressure, the blood-will interference of someone who wants incompatible things." She pressed harder against the concrete. "And it has a secondary characteristic I didn't mention because I wasn't sure of the read. A buried frequency structure that the practitioner is suppressing actively."
"Suppressing how," Mirae said.
"The way someone suppresses a frequency they know is detectable. Practitioners who carry lineage heritage sometimes learn to dampen the output — reduce the amplitude to below detection threshold — as camouflage. Goh taught this to settlement practitioners who had to operate in surface environments where detection would be dangerous." She paused. "The mole is suppressing their lineage frequency. Which means they carry one."
The basement was very still.
"Na Minjun," Seonghwa said. "A practitioner who entered the settlement network from the Gyeonggi community. Old way trained. Association access. And a suppressed lineage frequency." He looked at the ceiling. "Someone who's been living in both worlds."
"Someone who might not have started in Jaehyun's service," Mirae said, picking it through. "If they carry the lineage frequency and found their way into the underground practitioner community genuinely — if they were real, before they were an asset—"
"And then Jaehyun found them," Hyunwoo said. From the stairs. "Or created them. Someone with the right background, the right access, the right blood." He paused. "Or someone who was in the settlement community and got turned."
"The conflict pattern," Jisoo said. "They've been in conflict for a long time."
The information sat in the basement.
A person with lineage heritage, living two lives, suppressing the part of their blood that would identify them to other practitioners, feeding the BTD with the locations of communities whose trust they'd earned. Planting evidence at a massacre scene. Coming within ten meters of Jisoo, of Seonghwa, of the blade's resonance, and suppressing their own frequency well enough that Jisoo hadn't detected the lineage connection until she'd been running the archived comparison for two days.
How tired you'd be. How much of your own blood would be in conflict if you'd been doing that for years.
"They were at Incheon before us," Seonghwa said.
"They had a shorter route from wherever they were operating," Hyunwoo said. "If they knew about Han Sookhyun through the Association intelligence track — through Bae's access to the investigation files — they knew about the Incheon address before we identified it."
"Which means they were watching to see if we'd find it."
"And when we did—" He stopped. Recalculated. "Or they weren't watching. They went to clean it regardless, because a loose thread that close to the massacre evidence doesn't stay loose." He was quiet. "Either way, they knew."
"We're close to a name," Mirae said. "Taeyoung is pulling the registration file. One hour."
"One hour," he agreed.
He stood and walked to the northeast corner — not to read anything, just to move. The paramedic's physical habit: when the thinking ran ahead of the evidence, walk, let the body's motion balance the mind's forward movement.
The second section was complete. The remedy was understood. Soyeon was committed. The third section still waited in the blade's encoding — the activation sequence, the specific interference pattern that the remedy required, the operational instructions for doing the thing that Serin had built the blade to enable.
He needed the third section. He needed the third section soon, because Eunji was getting closer, and every chord session was a signal, and the mid-session locked state of the second section had been bleeding ambient frequency into the basement for eighteen hours.
He needed Ganghwa Island, because Han Sookhyun's sealed envelope might have the massacre evidence that they couldn't find anywhere else.
He needed Na Minjun's full identity, because Asset Meridian was the associate and the associate was the third responder and the third responder had placed the blood evidence that had put him on death row.
Three threads. One hour.
"Jisoo," he said.
She was reading the floor. "Eunji," she said, before he could ask.
"How close."
"The ambient frequency in the district has been elevated since yesterday morning." She pressed both palms flat. "She's been moving through the Mapo-gu area. Not stationary. The signal pattern suggests active monitoring — she's driving the coverage zone rather than holding position." A pause. "She hasn't queried the tributary network. She hasn't deployed sensors in the building infrastructure. She's running passive."
"She knows we're in this district," he said.
"She knows we're in this district." She looked at him. "She hasn't called in a team."
The sentence sat there.
"She drove past this building the day after the second session," Jisoo said. "I felt her sensor at thirty meters, passive, from the northwest corner. She was within direct detection range and she kept driving."
Hyunwoo came down the stairs fast. "What."
"She was at this building," Jisoo said, without inflection. "Two days ago. She knows where we are."
"And she hasn't moved on us," Seonghwa said.
"She hasn't moved on us."
The room absorbed this.
"She's running her own investigation," Mirae said slowly. "She's not going to be stopped by Bae suppressing the historical archive request. She's a tracker. She tracks." She looked at Seonghwa. "She's getting closer to the same information we have. Through a different route."
"Or she's waiting for the third section." He thought about it. The quarry, the chord, the non-attack. Eunji reading the inscription in the quarry stone. The organic sensor that had been with her since age twenty-three. The lineage frequency in her own blood that she'd compared against Bae's suppression document.
The same harmonic family.
"She carries the lineage frequency," he said.
"You knew?" Mirae's head came up.
"The quarry chapter. What she recorded in the BTD forensics report — the quality of her detection, the fact that she read *blood, remember, return* as a gwi-hwan inscription rather than an artifact anomaly. She knew what to look for because she understands it from the inside." He paused. "She's been running the organic sensor for fifteen years. She's been detecting blood-will practitioners. She's a lineage carrier who's been deployed to hunt lineage carriers."
"Which Bae knows," Hyunwoo said.
"Which Bae deployed deliberately." His blood stirred against the dual-state's resting baseline. "He put his best blood-will tracker on practitioner suppression and made sure she didn't have the information she needed to understand why her tracker was as good as it was. He's been using her frequency the way Jaehyun used Serin's frequency — as a tool, without her knowledge or consent." He paused. The parallel was uncomfortable in the way true things were uncomfortable. "She's been hunting her own blood."
The fluorescent buzzed.
"She didn't call in the team," Mirae said. "When she had us at thirty meters."
"No."
"What do we do," she said.
He thought about it. Han Sookhyun on the floor in Incheon, carrying information that got her killed. Eunji in a command vehicle two blocks away, not calling in the team. Jisoo with both palms on the concrete, reading the city's blood-will like a hand on a pulse.
"We leave her a message," he said.
Everyone looked at him.
"Not direct contact. Not yet. We leave a blood-resonance message in the tributary network at a frequency that someone with her sensor capability and her lineage heritage can read. Something that tells her what the blade carries. Something that explains why Bae doesn't want her to have the historical archive." He looked at Jisoo. "Can you encode a message at the lineage-carrier resonance frequency? Something that would be invisible to BTD sensors but legible to someone whose blood runs at that frequency?"
Jisoo was very still. "Theoretically. The lineage frequency is distinct from standard blood-will carrier frequencies. BTD equipment is calibrated for the standard spectrum. A message encoded at lineage-frequency amplitude would be noise to standard equipment and signal to a lineage carrier with an active organic sensor." She paused. "You're asking me to reach out to the person who's been tracking us."
"I'm asking you to leave a message she might find. What she does with it is hers." He looked at the stairs. "If she's questioning why she was deployed against people who share her blood — she needs to know she's not alone in asking that question."
Jisoo was quiet for three seconds. Then: "I'll need an hour. The frequency calibration for a lineage-specific encoding is precise work."
"One hour," he said. "Taeyoung's registration file will be here in one hour. Then we go to Ganghwa Island."
He went back to the cot and sat and looked at the blade. The sealed second section now complete. The third section waiting.
Somewhere in the city, Eunji was driving Mapo-gu's streets with her frequency humming and her journal in the glove compartment and the extraction team unsent, and she was getting close to the thing that Bae didn't want her to understand.
He hoped she was ready when she found it.
