The iron door to the interrogation room was tightly shut, but it couldn't contain the simmering anxiety within.
The smoke was thick and choking, turning the light bulb hanging in the air yellow.
Qin Dayong, one foot on the crossbar of the interrogation chair, held a cigarette butt in his hand, now just a stub, desperately trying to take one last drag.
"Smack!" The cigarette butt was slammed to the ground, sparks flying.
"Cry! All you do is cry! Why didn't you cry when you strangled your wife?"
Qin Dayong leaned halfway over the table, his dark face close to the man huddled opposite him: "Didn't work all afternoon, went to buy movie tickets, and then she died tonight. Liu Qiang, you're telling me it's a coincidence? I've seen that kind of thing a million times!"
Liu Qiang, sitting on the iron chair, was no longer human.
His face was smeared with snot and tears, his voice hoarse as if he'd swallowed sand, he could only mechanically shake his head.
"Innocent... Captain Qin, I really didn't... I just wanted to annoy her..." He repeated the same thing eight hundred times.
Qin Dayong's temple veins throbbed. He'd seen plenty of these stubborn cowards, never admitting defeat until faced with dire circumstances.
Just as he was about to resort to some methods, the heavy soundproof door creaked open.
Light streamed into the dimly lit room.
Gu Chen stood in the doorway, holding a chipped white enamel mug, steaming hot.
Qin Dayong turned around, his brows instantly furrowing into a knot: "Who let you in? Don't you know the rules? Get out!"
Gu Chen didn't back down.
He seemed not to hear the outburst, walking straight to Liu Qiang and placing the enamel mug beside the trembling man.
"Drink." His voice was low and emotionless.
But for Liu Qiang at this moment, this was a lifeline.
Extreme fear combined with prolonged screaming had left his oral mucosa dry and cracked.
Liu Qiang even forgot to thank him, grabbing the mug with both hands and, ignoring the scalding water, tilting his head back to gulp it down.
"Glug, glug." The swallowing sounds were rapid and greedy, water trickling from the corner of his mouth, wetting his greasy collar.
Gu Chen stood half a meter away, his gaze behind his glasses not on the water, but fixed intently on Liu Qiang's Adam's apple and wrist.
Qin Dayong was about to explode when he noticed Gu Chen raise his hand, making an extremely subtle "pressing down" gesture.
It was a signal only experts would understand—reading someone.
Liu Qiang had drunk too quickly, coughing and choking, his whole body curled up like a shrimp, the violent coughing making the handcuffs rattle.
Gu Chen withdrew his gaze and turned.
He looked at the furious Qin Dayong, his tone as calm as reporting the weather: "Captain Qin, release him."
Qin Dayong, who was about to put his second cigarette in his mouth, froze in mid-air upon hearing this.
"What did you say?" He laughed angrily, as if he'd heard the funniest joke. "Gu Chen, do you think this criminal investigation team will belong to you if I don't get angry?"
He grabbed Gu Chen's collar and shoved him so hard his back slammed against the wall.
"The chain of evidence is complete! Motive, physical evidence, timing—everything's there! You think I'll release him just because he drank some water? You think this is child's play?"
Gu Chen didn't struggle.
He simply raised his hand and slowly pried Qin Dayong's fingers apart one by one, straightening his police uniform collar.
"If it's a murderer who's just committed a killing, their adrenaline is still wearing off. During interrogation, they'll instinctively be wary, sip water slowly, and their eyes will dart to the upper left—those are physiological characteristics of someone fabricating lies." Gu Chen pointed to Liu Qiang, who was still coughing violently.
“But he didn’t. He held the cup with his hands clenched inwards—a childlike defensive posture born of extreme insecurity. His first reaction after choking on water is to find a corner to hide in, not to observe your reaction.”
“This is a terrified mouse, not a wolf that just killed someone.”
Qin Dayong paused, then waved his hand impatiently: “Stop giving me this foreign talk! Psychology as evidence? I only believe physical evidence! How do you explain that movie ticket?”
“That was bait.” Gu Chen stared directly into Qin Dayong’s bloodshot eyes, unyielding.
“The movie ticket was dry. In that downpour, there’s only one possibility—the murderer deliberately placed it there for you to see during a break in the rain.”
“He’s waiting for you to catch Liu Qiang. The longer you linger here, the safer he is.”
Qin Dayong’s chest heaved violently.
Reason told him this kid was talking nonsense, but experience told him that giving up a suspect he had already caught was dereliction of duty.
“Fine.” Qin Dayong threw the cigarette he had just lit on the ground and crushed it out with his toe.
"Since you're so amazing, let's make a bet."
"If it turns out Liu Qiang didn't commit murder, I'll do whatever you say from now on."
"If Liu Qiang is the murderer..." Qin Dayong took a step closer, his eyes flashing with malice, "You get out of the police station right now, and never let me see you in that uniform again!" Gu Chen pushed up his gold-rimmed glasses, the lenses reflecting a cold light.
"Twenty-four hours."
With that, he turned and opened the iron door, disappearing into the darkness of the corridor without looking back.
...The Archives.
This was a forgotten corner of the police station, filled with the smell of mildew and dust.
Gu Chen pulled out a wooden table with peeling red paint and spread out an old map of Nanjiang City surveyed in 1980.
A Hero brand fountain pen was full of ink, its nib hovering above the map.
He closed his eyes.
The gates of his mind swung open.
Thirty years of criminal investigation experience, combined with all the details of this serial case from his past life, were like shattered puzzle pieces frantically piecing together in this moment.
The pen tip fell.
"Swish, swish, swish." The strokes were incredibly fast, like a scalpel cutting through flesh.
Gu Chen didn't look at the map; he was drawing another map—a "hunting ground" that existed only in the mind of that deranged killer.
The leather factory in the west of the city, the Nanjiang River embankment, the willow grove, the undeveloped abandoned buildings, the entrance to the abandoned air-raid shelter…
Black lines meandered across the map, eventually connecting these seemingly unrelated locations into a bizarre geometric shape.
"He's drawing a circle." Gu Chen stared at the unclosed ring, muttering to himself.
He turned and walked to the deepest part of the filing shelf, the dead corner where "long-unsolved cold cases" were stored.
His fingers brushed away a thick layer of dust, pulling out a yellowed kraft paper bag.
[July 12, 1978, Missing Person: Chen Xiaoya. Textile factory worker.] Gu Chen opened the file, his fingertip pausing on the black-and-white passport photo.
The girl wore a white polyester shirt, the collar revealing a small section of the lining—deep red.
Textile worker, red lining, disappeared on a rainy night, slightly limping left leg due to a work injury.
Then looked at Li Hongmei.
Leather factory worker, red skirt, died on a rainy night, born with a slightly limping left leg.
This wasn't some drunken passion murder.
This was a five-year-long serial hunt.
The killer had severe obsessive-compulsive disorder; he was waiting, waiting for a specific period, waiting for a sufficiently heavy rain, waiting for prey that matched his twisted aesthetic.
"Thump." The door was pushed open.
Qin Dayong stood in the doorway, clutching a fax paper, his knuckles white.
He didn't speak, his face darker than the rainy night outside.
Gu Chen's pen didn't stop; he heavily scribbled a dot of ink at the gap in the map.
"Speak." One word, taking control.
Qin Dayong took a deep breath, his chest heaving like a broken bellows.
“Just received a notification for assistance.”
“Old Liu from the leather factory's security department has sobered up.” Qin Dayong's voice was dry, as if forced out of his throat. “He vouched for it with his party membership; from eight to ten last night, Liu Qiang was drinking with him in the guard room. He got drunk and collapsed on the floor of the duty room, not moving an inch.”
“Old Liu was right there watching, not leaving his side for a moment.”
Dead silence.
Only the sound of rain pattering against the glass outside the window.
Qin Dayong's usual arrogant demeanor deflated like a punctured balloon.
They really arrested the wrong person.
The whole team had mobilized and worked all night, only to be seen through by this gatekeeper through a crack in the door.
The sense of defeat was worse than being slapped twice.
Gu Chen finally put down his pen.
He capped his pen, looked up from the map, and stared at the tall figure at the door. “Captain Qin.” Gu Chen’s voice held no sarcasm, nor the joy of victory; it was chillingly calm.
“Release him.” Qin Dayong didn’t move.
His gaze passed over Gu Chen’s shoulder, fixed on the densely drawn map on the table.
Red ink formed lines, carving wounds across the map of Nanjiang City.
Especially the abandoned air-raid shelter, highlighted prominently, sent chills down Qin Dayong’s spine—it was a place that had “disappeared” from the files five years ago. How did this kid know there was a road there?
“Gu Chen.” Qin Dayong took a step forward, his voice trembling, revealing an undisguised fear and confusion.
“What exactly were you doing in this dilapidated archive room…”
He pointed to the pile of old papers.
“What did you see?” Gu Chen adjusted his glasses, picked up the old file from 1978, and gently patted it in front of Qin Dayong.
Dust danced in the lamplight.
“What I’m seeing isn’t a file.” Gu Chen pointed to the smiling girl in the photo, his eyes sharp as knives, slicing through the mists of time.
“It’s blood that hasn’t dried yet.” He stood up, walked to the map, and tapped his finger heavily on the ink dot he had just drawn.
“Captain Qin, Liu Qiang is just a smokescreen.”
“The killer hasn’t stopped; he’s celebrating the police’s stupidity.” Gu Chen turned his head, his eyes behind his gold-rimmed glasses radiating a chilling certainty.
“Moreover, his next target has already been chosen.”