The printer stopped.
Hae-in and Kang stood in the middle of the corridor.
Neither moved.
The detention officer looked toward the security room.
"There's a printer down there."
Kang turned to him.
"Take us."
They followed him through a narrow passage.
The security room was empty.
Monitors covered one wall.
Most showed the detention center's corridors.
One showed Cell Seventeen.
Another showed the service elevator.
Another showed the outside gate.
The printer sat beneath the monitors.
A single sheet of paper rested in its tray.
Kang picked it up.
Hae-in looked over his shoulder.
It was a security report.
CELL BLOCK C — INCIDENT REPORT
TIME: 23:14
Kang checked his watch.
"23:02."
"Twelve minutes."
Hae-in took the paper.
The report described an incident that had not happened yet.
23:08 — Officer enters Cell Seventeen.
23:10 — Unauthorized individual detected.
23:12 — Officer unconscious.
23:14 — External access confirmed.
Kang looked at her.
"This is impossible."
"No."
She turned the page over.
There was handwriting on the back.
Don't interfere with the sequence.
Kang stared at it.
"Sequence?"
Hae-in folded the paper.
"We're leaving."
The officer looked relieved.
Then the alarm sounded.
A sharp tone filled the building.
Red lights flashed along the corridor.
The officer's face went pale.
"What's happening?"
Kang grabbed his radio.
"Control, report."
Static.
Then a voice.
"Cell Block C security breach."
Kang looked at Hae-in.
She looked at the clock.
23:08.
Exactly as the report predicted.
The door opened.
An officer rushed inside.
"Cell Seventeen!"
They ran.
The cell door was open.
The officer who had accompanied them lay on the floor outside.
Unconscious.
Kang immediately checked his pulse.
"Alive."
Hae-in looked inside the cell.
Empty.
Again.
But something had changed.
The metal bed had been moved.
Only a few centimeters.
Enough to reveal a narrow opening in the wall.
Hae-in crouched.
"There."
Behind the bed was a small metal panel.
Kang pulled it open.
Inside was a cavity.
Not large.
But deep enough to hide documents.
Hae-in reached inside.
Her fingers touched paper.
She pulled out a bundle.
Old files.
Dozens of them.
Every folder had the same marking.
C-17.
Kang stared.
"Someone built a hidden archive inside this cell."
Hae-in opened the first folder.
A photograph.
A name.
A date.
Then another.
And another.
Seven files.
She spread them across the floor.
The same seven names from Soo-jin's notebook.
But there was something different.
Each file contained a photograph of the person before they disappeared.
The first six had a red stamp.
TRANSFERRED.
Park Min-jae's file had no stamp.
Instead, someone had written:
FAILED.
Hae-in's eyes narrowed.
"Failed?"
Kang opened the file.
Inside was a single report.
He read silently.
Then looked at her.
"What?"
"He wasn't supposed to escape."
"Escape from where?"
Kang handed her the report.
Hae-in read it.
Her expression changed.
The document wasn't from a police department.
It wasn't from the detention center.
It had no official letterhead.
Only a symbol.
A black circle crossed by three lines.
At the bottom was a sentence:
SUBJECT PM-07 FAILED TRANSFER. RETAIN FOR SECONDARY PROCESSING.
Hae-in read it again.
"Subject."
Kang nodded.
"They weren't treating him like a prisoner."
"No."
She looked at the other six files.
"They were treating all seven of them like subjects."
A sound came from the corridor.
Footsteps.
Kang immediately stood.
"Someone's coming."
Hae-in gathered the files.
"Take the original report."
They switched off the flashlight.
The footsteps approached.
Slowly.
A shadow appeared beneath the door.
Stopped.
Neither of them breathed.
The door handle moved.
Once.
Twice.
Then stopped.
A voice came from outside.
"Detective Seo."
Hae-in recognized it.
The warden.
She looked at Kang.
He shook his head.
Something was wrong.
The voice came again.
"Open the door."
Hae-in didn't answer.
The warden spoke more quietly.
"You shouldn't be inside."
Kang moved toward the door.
Hae-in caught his arm.
"Wait."
"What?"
She pointed at the floor.
The shadow beneath the door wasn't shaped like the warden.
It was too tall.
Too thin.
And there was no second shadow from the corridor lights.
The person outside wasn't standing in the corridor.
They were standing directly against the door.
Hae-in stepped backward.
The handle moved again.
Then—
silence.
When they finally opened the door, nobody was there.
Only a small envelope lay on the floor.
Hae-in picked it up.
Her name was written on the front.
Inside was one photograph.
Her father.
Standing beside Cell Seventeen.
But the photograph wasn't eight years old.
The timestamp on the bottom read:
THREE DAYS BEFORE HIS DEATH.
Kang stared at it.
"Hae-in..."
She didn't answer.
Her father was standing outside the cell.
And beside him was Park Min-jae.
Alive.
The photograph had been taken three days before the murder.
On the back, someone had written:
YOUR FATHER DIDN'T FIND THE SEVENTH.
A second line appeared beneath it.
HE WAS LOOKING FOR THE EIGHTH.
Hae-in slowly lowered the photograph.
For the first time since the investigation began, she felt something she couldn't immediately turn into evidence.
Fear.
Not for herself.
For what her father had been involved in.
And for the possibility that the person they had been searching for...
wasn't Park Min-jae at all.
It was someone else.
Someone her father had known.
Someone who was still alive.