"How close," Seonghwa said.
He was dressed in thirty seconds. The door was open and Jisoo was in the hallway with the blade wrapped in cloth against her chest, both hands at the grip she used to read ambient data without transmitting.
"She's in the Suwon-Anyang network," Jisoo said. "South of the river. She's reading north — she has Serin's ambient frequency as a directional signal. The frequency propagates through the tributary channels and she's following it upstream."
"She's not in the city yet."
"No. But the tributary network is fast for someone who knows it. She knows it." Jisoo looked at him. "She's a practitioner. She can move through the channels the way we do."
"How long."
"Two hours before she has enough data to narrow the location to district level. Less if she finds a junction with a recent strong reading — the partial treatment in Gwangmyeong, the Dobong chord event, they're both in the substrate. She's following the signal trail." She paused. "She knows she's following Serin's frequency because she knows Serin's frequency. She's dealt with the old network for fifteen years."
He looked at the clock. Three-eighteen AM. Three hours and forty-two minutes until the Taeyoung annex opened for their access window.
"Wake everyone," he said.
---
They were moving in eighteen minutes.
Not the full group — Eunji and Soyeon went to a separate location, a coffee shop that opened early in Yeongdeungpo, somewhere with an institutional environment that would read as legitimate activity in the Association's surveillance feed for Eunji's tag. They'd been registered at Roh's store for too long. The passive BTD scan had confirmed the Dobongsan area. Staying in the same building until six was a structural risk regardless of Blue Ridge.
Mirae had the medical kit. Hyunwoo had his contacts. Jisoo had the blade.
Seonghwa stood in the convenience store's doorway and told Roh: "You've been helpful. If someone comes looking for who stayed here — three days ago you had two document contractors in the upper room. You don't remember their faces. You never learned their names."
"I never learn names," Roh said. He was eating instant noodles at three AM without apparent interest in the situation beyond its practical terms.
They went.
---
The route Hyunwoo had mapped used Dobongsan's residential network — the narrow streets between apartment blocks, the service roads, the infrastructure corridors that weren't footpaths but weren't quite roads either, the urban tissue of a neighborhood that had been layered over older geography. Through the Blood Sense's passive mode, Seonghwa could feel the tributary network running under the concrete — the old-way channels that Jaehyun had maintained, the substrate that Jisoo had been reading since Gwangmyeong.
"She's moved north," Jisoo said. She had one hand on the blade, one hand tracing the walls of the alley they were moving through. "She's in the Han-southern network. She's fast."
"She's used the tributary channels before," Seonghwa said.
"Yes. She knows the access points." Jisoo was quiet for a few steps. "She's reading the chord's residue in the Dobong substrate — the forty-seven seconds, the dual-state at full amplitude. It's the biggest blood-will event in this area in years. She's following it like a scent trail."
"Can Serin reduce the blade's ambient transmission."
A pause. Jisoo's hand pressed the cloth around the blade. "She says yes. She can pull back to below the detection threshold Park Soyoung uses for passive scan. She's been at near-minimum for a hundred and sixty-seven years — she knows how to suppress output." She paused. "But if she suppresses, I lose my read on Soyoung's position. We go blind."
"Option B."
"I keep a directional read on Soyoung's scan frequency — not the blade's output, but the echo. When she scans, the scan has a signature. I can read the signature without Serin needing to be active." She paused. "It means I'm reading her scan rather than her source. The resolution is lower. I get direction, not position."
"Do that."
Jisoo closed her eyes for five steps, walking by touch and the peripheral body awareness that fifteen years of old-way training produced. Then she opened them. "Done. The blade is below her detection threshold. Her scan frequency is — east-northeast. She's reading toward Dobong-gu proper. She's not in our current position corridor."
"She'll reach Roh's building."
"In about twenty minutes."
Roh's building. Which was now empty. Which held no practitioners, no blood-will signals, no evidence of anything except two contractors who had been in the upper room three days ago and whose faces Roh didn't remember.
Twenty minutes was going to be close.
---
They cleared the Dobongsan residential corridor at three fifty-two and descended into the 1 line's northern terminus. No passive BTD scan units visible — Jisoo was monitoring. She'd been monitoring since the alley and her face held nothing — reading multiple channels simultaneously, expressing none of them unless asked.
On the platform, standing against the far wall while the late-night service ran its extended interval:
"She's at the building," Jisoo said. Flat. "She's running a full-amplitude scan of the building's substrate. She's not finding what she expected." A pause. "She knows we were there. The residue is in the floors — days of extended blood-will presence, the Serin blade's output, practitioners sleeping in those rooms." She pressed the wall. "She knows we left within the past hour."
Mirae said nothing. She had the medical kit on one shoulder and her other arm through Seonghwa's and she was watching the subway tunnel the way she watched things when she was processing and didn't need to speak.
"She won't follow into the transit system without knowing direction," Jisoo said. "The transit substrate is too fragmented — the concrete and steel and the electrical field disrupts blood-will reading below a hundred meters. She'd need a surface read to track us." She paused. "We're clean if we stay underground."
"We can't stay underground until six AM."
"No." She pressed. "She's scanning north from the building. She thinks we went deeper into Dobongsan. She'll find the junction site residue." A pause. "She's going to realize the junction event was last night. Not yesterday, not recently — last night."
Which meant she'd know the practitioners who completed the chord had moved south, not north.
Which meant she'd redirect.
"She'll be in the southern transit network within twenty minutes," Jisoo said. "She'll be scanning for the blade's frequency. Which she won't find because Serin is suppressed." A pause. "But she'll find the echo of my scan frequency. If she's good enough to read scan echoes."
"Is she."
"She reads the network the way I do. If I'm good enough to read her scan echoes, she's good enough to read mine." Jisoo looked at him. "We have a window. Yeongdeungpo is forty minutes south. If we move now and she redirects south in twenty, we have twenty minutes of lead."
"That's not a lot."
"No." She pressed harder against the wall. "But the annex has institutional shielding. If we're inside the shielding before she gets within scan range, we disappear from her read entirely." She looked at the tunnel. "Like a practitioner who entered a vault and the vault closed behind them."
The train arrived.
They got on.
---
They were through Taeyoung's building access at five forty-seven AM.
The institutional shielding wasn't the annex's shielded evidence room — that was two floors down, accessed through a secondary clearance corridor that required Taeyoung's personal authorization code. It was the building itself: the 1990s construction that had been building up years of blood-will absorption, the Association-grade materials that attenuated field propagation, the forty centimeters of concrete and steel that stood between the outside network and the evidence archive.
Good enough.
Jisoo pressed her palms to the lobby's wall at five-fifty AM and read the external field.
"She came south," she said. "She's in the Yeongdeungpo network. She's scanning for the blade." A pause. "She can't find it. The building's shielding is holding." She pressed harder. "She can tell there's something behind the shielding. She knows the frequency she's tracking went dark in this district. But she can't resolve it through the building." She looked at Seonghwa. "She'll wait."
"For how long."
"For as long as it takes." Jisoo looked at the floor. "She's patient. She's been patient for fifteen years."
Taeyoung met them at the secondary clearance corridor at five fifty-nine. He looked at them — the three AM movement, the full medical kit, the blade in Jisoo's arms, the general condition of people who'd spent two hours navigating the city ahead of a tracker — and he didn't say anything about it. He ran his authorization code. The corridor opened.
The shielded room was cleaner than the Uijeongbu panic room. Four walls with uniform attenuation, the geometric proportions closer to square, the installation showing the kind of professional calibration that came from a contractor who'd done this under specification rather than improvisation. Mirae walked around it twice, checked the monitor readings, checked them again.
"This works," she said. "This is better than anything we've had."
She set up the full protocol. Jisoo sat in the center. Seonghwa let the dual-state settle into working configuration.
Twenty-two minutes. Full amplitude. The healing frequency built and held, the standing wave geometry clean and consistent, the Blood System engaging without the spike — operating within the protocol's established parameters, learning the routine of it.
Jisoo sat in the center and received it without complaint.
Afterward, she sat for four minutes with her palms on the floor.
"Better," she said finally.
Mirae made notes. "This room. Daily. Six weeks minimum." She looked at the walls. "After today, we establish a transmission protocol for the session data so Dohan can cross-reference with the Gwangmyeong cohort. The full treatment development requires both datasets." She looked at Taeyoung. "Access will be authorized."
"It's authorized," he said.
Jisoo opened her eyes slowly. She pressed the floor. "Serin has something she wants to say."
The room went quiet.
"About the junction dismantling pattern," Jisoo said. Her voice shifted — the old-form cadence, measured and deliberate, Serin running her transmission at reduced amplitude through the blade's restored awareness. "I have been reading the network for a hundred and sixty-seven years. What your reader described as a pattern — it is a pattern. It is a methodology."
She paused.
"The junctions that were dismantled — I know each one. I watched each one. The practitioners who died, the practitioners who disappeared, the practitioners who fled without knowing why they were being targeted." The cadence was even. "The methodology is old. Older than the Hunter Association. Older than the modern awakening framework. It is the same methodology used in the Joseon period, in the Japanese period, and before that." A longer pause. "The old-way network was dismantled once before. Three hundred years ago. The practitioners who rebuilt it — my generation, my teachers — spent a hundred and fifty years recovering from it." She paused. "I have been watching the same pattern begin again for fourteen years, and I have been in a bone blade unable to speak."
Seonghwa looked at the blade.
"The person running this dismantling — Blue Ridge, as you call her — is not acting alone and is not acting for the Association specifically. The Association is a mechanism. She is using it as a mechanism." Another pause. "I can give you the name she uses in the old-way network. Not the name your investigation knows. The older one."
Jisoo looked at him.
"Tell me," he said.
And Serin told them the name that had been in the blood-will network since before the Hunter Association existed.
Outside the building, in the Yeongdeungpo tributary channels, Park Soyoung waited with the patience of someone who had done this before.
She had done it before.
She would wait.
