Morning came too quickly.
Soft golden sunlight slipped through the blinds and stretched across Yuna's desk, but she hadn't moved much since she sat down. Around her, the headquarters had returned to life—phones ringing, officers exchanging reports, footsteps echoing through the corridors. Yet none of it reached her fully. Her world had narrowed to a single point.
Mina's father.
The two senior officers.
Room 8.
The same three threads kept circling in her mind, refusing to separate.
"Something's off…" she murmured under her breath.
Her fingers moved across the keyboard as she pulled up the surveillance logs again. The timestamp from Room 8—the one that had bothered her last night—was still there. Unchanged at first glance.
But the longer she stared, the more something felt wrong.
She leaned closer, eyes narrowing slightly.
"…Wait."
The timestamp matched.
But the footage ID code didn't.
Her heartbeat stilled for a second before picking up again, faster this time.
"Who edited this…?"
Before she could investigate further, a notification popped up on her screen.
[Case File Uploaded: Internal Archive – Restricted Access]
Yuna blinked, confused. "I didn't request anything…"
Still, she clicked.
The file opened slowly, almost hesitantly, as if revealing itself piece by piece. Her eyes scanned the contents quickly—location, witnesses, assigned officers—and then suddenly stopped.
Her fingers froze above the keyboard.
Victim Name: Han Seojin.
The air in the room seemed to vanish.
"…Dad…?" Her voice came out barely above a whisper.
Her chest tightened as she scrolled further, her vision sharpening with urgency. The names of the assigned officers appeared next—and her breath caught again.
They were the same.
The same two senior officers currently involved in Mina's case.
Her mind raced as she continued reading, searching for answers, for something—anything—that made sense.
But the conclusion only made it worse.
[Cause: Unidentified. Case Closed.]
Closed?
Her grip tightened on the edge of the desk.
"No… this doesn't make sense."
If her father's case involved those officers…
If Mina's father was somehow connected…
Then this wasn't coincidence.
It was a pattern.
A cover-up.
"Yuna."
She flinched.
Joon stood beside her desk, his presence so sudden she hadn't even heard him approach.
"…You okay?" he asked, his gaze quietly studying her face.
For a split second, she hesitated. Then she minimized the file.
"Yeah. Just didn't sleep properly."
His eyes lingered, as if weighing her answer. Like he knew there was more she wasn't saying. But as always, he didn't push.
"Briefing in five," he said calmly.
She nodded. "Got it."
He turned to leave, but paused for just a moment before walking away.
"Don't overdo it today."
Her expression softened slightly. "…I won't."
But the second he was gone, she reopened the file—faster this time, urgency replacing hesitation.
There had to be more.
There had to be something they missed.
Her eyes moved rapidly across the screen—
And then it flickered.
Once.
Twice.
And suddenly—
The file disappeared.
Yuna stared at the blank screen, her pulse roaring in her ears.
"No… no, no—"
She searched the archive again.
Nothing.
No file.
No trace.
As if it had never existed.
A chill crept down her spine.
Someone had sent it.
And then erased it.
Which meant—
Someone knew she was looking.
Across the hall, Joon stood near the window, his phone pressed to his ear.
"Yeah," he said quietly. "I need access to an old case file."
A brief pause.
"Eleven years ago. Unresolved. Victim—Han Seojin."
Silence stretched on the other end.
Joon's expression slowly hardened. "…You're telling me it doesn't exist?"
His jaw tightened slightly. "Check again."
Another pause followed before he exhaled softly. "…Got it."
He ended the call but didn't move immediately.
Something about that name felt familiar.
Too familiar.
And he didn't like the feeling settling in his chest.
Not one bit.
Back in her department, Yuna sat still, her thoughts spiraling faster than she could control.
Then—
A soft sound.
Click.
Her head snapped toward the glass door.
It was closed.
But she didn't remember anyone entering—or leaving.
"…Hello?" she called out.
No response.
The room felt different now. Quieter. Heavier.
Her gaze slowly shifted back to her desk.
And that's when she saw it.
A small black envelope lay beside her laptop.
Her breath hitched.
"I didn't—"
She reached for it slowly, her fingers brushing against the smooth surface. It was light. Unmarked.
Except for one thing.
Her name.
Han Yuna.
Written in clean, precise handwriting.
A faint unease settled in her chest as she opened it.
Inside was a single folded sheet of paper.
She unfolded it carefully.
Her eyes scanned the first line—
And froze.
"Stop digging into Room 8."
Her grip tightened slightly.
Then her gaze dropped to the line below.
"Or you'll end up like him."
For a moment, everything went still.
The noise outside, the movement in the station, even her own breathing—
It all faded.
The paper trembled faintly in her hand.
Not from fear.
From something colder.
Her jaw clenched slightly as her expression hardened, the softness from last night completely gone.
"…Try me," she whispered under her breath.
Somewhere beyond the glass walls of the department, hidden within the very system she trusted—
someone had already made their move.
And this time—
Yuna wasn't just investigating the case.
She had become part of it.
[End of Chapter 10]