A Perfectly Prepared Scenario
Two days after the incident. Monday.
The investigation opened with a complete reconstruction of Park Ajeong's movements on the day of the murder. Everything checked out, exactly as she had claimed. The interior CCTV from the coffee shop, pulled by Violent Crimes Team 1, gave her an airtight alibi. In the window before and after the estimated time of death, she never once left her seat. The timestamp on her receipt matched to the minute.
While her father was dying, Park Ajeong had been sitting in a coffee shop, playing a game on her phone. Legally, she was nothing more than a perfect witness.
Three days after the incident. Tuesday.
The investigation turned, almost of its own accord, toward the man who had been with her that morning — Lee Doyun, the one who lived next door to Oh Sae-ah. Overnight, the analysis team had pulled the villa building's CCTV. The footage was sharp and unambiguous: the two of them leaving the house together on the morning of the murder.
After splitting off from Park Ajeong, he headed toward the traditional market. A public camera at the market entrance caught him walking in. After that, his trail went cold. And as it happened, the alley where the killing took place sat inside that same market — one of the vast CCTV blind spots carved out by the tangle of shops and street stalls packed in on every side.
Roughly twenty minutes later, a figure presumed to be Lee Doyun — the ghost on the cameras — reappeared at the exit on the opposite side of the market. That was the sum total of what the police had. Circumstance, and nothing else: he had gone into the blind spot, and he had come back out. Of what he had actually done in the interval, there was not a single piece of direct physical evidence.
In a courtroom, his lawyer would say it without breaking a sweat.
Oh Sae-ah stood in front of the investigation board. Park Ajeong's photograph. Lee Doyun's photograph. Between them, a single solid line: Left the house together that morning. Everything else was a faint scatter of dotted lines — suspicion without a scrap of proof behind it.
Four days after the incident. Wednesday.
The canvassing operation under Squad Leader Park hit a wall of its own. Park Kyung-chul's relationship with his daughter had been every bit as poisonous as the neighbors described — but that was old history. Of any recent blowup, any threat, any decisive rupture between the two of them, there was no evidence anywhere.
Worse, the scene itself had given them nothing. The killer had left behind not a single strand of hair, not a single fiber — nothing but the victim's own blood. The murder weapon was gone, of course. The alley was a blind spot. All the police possessed was the medical examiner's finding that the victim had been stabbed with an awl-like instrument, and a blurry shot of a suspect's back. Everything else dissolved into fog. Circumstantial. All of it.
Five days after the incident. Thursday night.
Oh Sae-ah stood alone before the investigation board in the empty Violent Crimes Team 1 office. The board had grown into a vast spiderweb, radiating outward from Park Kyung-chul's photograph at the center. Faces branched off from every grudge in his life — loan sharks, rival gang members, even his mistress's ex — and they covered the wall from edge to edge. The rest of the team had been running on no sleep for days, each of them digging into a suspect of their own.
But Oh Sae-ah's eyes were fixed on two photographs stuck at the outer fringe of that web, as if they barely mattered. Park Ajeong. Lee Doyun. To everyone else on the team, they were a reference witness with an airtight alibi and Pedestrian 1 — most likely a ghost of unknown identity. In Oh Sae-ah's mind, they were the only truth the case had.
She wiped every other suspect off the board and drew invisible dotted lines around those two faces alone. A witness with a perfect alibi. A ghost who existed and could not be caught. It was still a hypothesis that belonged to her and no one else. There was nowhere near enough evidence to move on it. Her instinct was screaming itself hoarse, and her reason was holding the whole thing down.
The two of them were using each other as shields, claiming perfect innocence from behind the iron fortress of the law. And Oh Sae-ah was still lost in the labyrinth, unable to find even a single crack that could bring that fortress down.
The next morning. Friday.
The air in the Violent Crimes Team 1 office hung heavy with defeat. Despite the all-nighters, the loan shark who had looked like a prime suspect and every acquaintance tangled up in money had produced a perfect alibi. The investigation was back at zero.
Oh Sae-ah stared at the board with empty eyes. Among all those faces, her gaze was still locked on Lee Doyun, stuck at the edge.
"Hahh..."
She let out a long breath and spoke to Squad Leader Park, who was sorting reports beside her.
"Lee Doyun. Let's bring him in for a witness interview."
Squad Leader Park looked up, puzzled.
"Lee Doyun, you mean?"
The question underneath was plain enough. They had no shortage of real suspects. Why waste time on a kid they had nothing on?
"Yes."
Her voice was flat and final. She pointed at Lee Doyun's photograph.
"He's Park Ajeong's only known associate. And he's the only person whose description matches the young man the witness reported. We can't rule him out just because the cameras never caught his face."
She looked Squad Leader Park in the eye.
"Bring him in. I need to see him myself."
Pathetic.
That was the first thing Oh Sae-ah felt when she finally stood in the same room as Lee Doyun. Slumped shoulders. A head hung so low it nearly touched his chest. A walk so drained of confidence it looked like he might sink through the floor. He came to a halt in front of the chair without once managing to meet her eyes. The old T-shirt hanging off him made his skinny frame look even smaller.
She looked him over in silence. This was the ghost who had moved through the CCTV footage without a single wasted step? The one who had put a weapon through a man's kidney with surgical precision and pumped him full of chemicals?
Impossible.
An alarm went off somewhere behind her eyes. The profile they had built from the data and the person standing in front of her did not belong to the same species.
"Please, have a seat."
He startled as if the words had been a gunshot and folded himself awkwardly into the chair, staring down at his own fingers on the tabletop.
A terrified little mouse.
She watched him for a moment. Then she put every trace of suspicion away and asked her first question in a voice gone deliberately soft.
"Mr. Lee Doyun."
"Yes."
"What is your relationship with Ms. Park Ajeong?"
"Uh... um... I dunno? I'm not really sure?"
Déjà vu cut through her like a blade. A few days ago. The same question. The same answer. Park Ajeong's vacant face.
I don't know.
I said I don't know.
"Aren't the two of you living together?"
She asked it the way you confirm a fact already in the file. He shrugged and mumbled at the floor.
"Well, it just kinda happened...?"
"May I ask how you came to meet Ms. Park Ajeong?"
"Um, just... by chance?"
Something was wrong. Her brow drew together. The whole performance was wretched — cowed, pitiful, so thoroughly unthreatening it barely registered as a human presence. Every inch of him was broadcasting the same message: I am a weak creature who knows nothing.
But his eyes bothered her.
His body shook like a herbivore that had caught the scent of a predator. And yet, in the sliver of a second when he lifted his head and their gazes actually met, those eyes were not vacant the way Park Ajeong's had been. They were not frightened, either. Buried in them, faint but unmistakable, was the cold look of someone who was watching everything.
A chill ran the length of her spine.
His gaze, which had been resting on the table, flicked for an instant toward the ordinary ballpoint pen sitting in front of her — and the look made her skin crawl. It was not a threat. It was not even strange, not in any way she could have written down. It lasted less than a heartbeat. But it was not how a person looks at an object. It was the look of someone who already knew the pen's weight, the texture of it, and exactly what could be done with it.
Her hand was trembling, just slightly, when she picked the pen up and slid it into her jacket pocket without a sound. Lee Doyun did not react. He dropped his head again and went back to chewing his nails, still wearing the face of a man about to come apart.
Is he acting?
She didn't know. The confusion sat in her chest like something wet. She wiped her palms — damp for no reason she wanted to name — against her slacks and assembled the next question in her head.
"All right. Then how about this. Have you ever met Ms. Park Ajeong's father — Mr. Park Kyung-chul?"
She pinned his face with her eyes and waited. He gave her nothing. Then he shook his head, still unable to look at her.
"No."
A few more questions came and went after that. None of them landed. Every one of them disappeared into the strange, bottomless indifference he carried around like a coat. His relationship with Park Ajeong was still I don't know. His job was I don't have one. His reason for going to the market that day was just because. He held the clumsy, frightened act from the first minute to the last, and he did not give her a single thing she could use.
She stood.
"I understand. You're free to go for today. We may need you for further questioning, however, so please don't leave Mujin City for the time being."
"Y-yes..."
He nodded too many times, scrambled up from the chair, and hurried out of the interrogation room.
Click.
The door shut. Oh Sae-ah and Squad Leader Park were the only ones left. In the heavy quiet, he let out a short, incredulous laugh.
"Aigoo... Team Leader. Just looking at a guy like that sucks the life right out of you. Are all the twenty-year-olds like that these days? One tap and he'd snap in half..."
He dragged his pen through the name Lee Doyun on the file and muttered to himself.
"A total wash. Completely empty. Won't be any help to the investigation at all."
To Squad Leader Park, Lee Doyun was a pathetic young man who could safely be ignored. Oh Sae-ah shook her head, quietly. Her eyes were still on the door he had gone through.
"No, Squad Leader."
Her voice was colder than it had been all week.
"That wasn't fear."
She added the rest under her breath, almost to herself. Whether he heard it, she couldn't tell.