A real killer playing a villain; the guy surnamed Zhen in Detective, run!

The on-duty police officer called Jiang Yan to confirm.

Three minutes later, Jiang Yan came downstairs herself.

She took out a temporary assistance personnel registration form and slapped it on the counter.

"Sign, put fingerprints, and turn off and seal the phone. The whole process was recorded, but the police were still primarily responsible for the interrogation; he only provided psychological support."

Before going upstairs, Lu Yuan saw several police reflective vests hanging on the coat rack and casually grabbed one to put on.

Jiang Yan turned around: "What are you doing?"

"Be compliant." Lu Yuan looked down at the reflective strip on his chest. "Otherwise, I'll look too much like a food delivery guy on the security camera later."

Jiang Yan's lips moved, but she didn't utter a curse.

On the basement floor, as soon as the door to the monitoring room opened, more than a dozen pairs of eyes turned to look at it.

Cui Lei was the first to stand up.

"Captain Jiang, are you crazy? Letting an actor interrogate a serial killer? Letting him into the interrogation room? Who's going to take the blame if something goes wrong?"

"I'll carry it."

"He's an actor!"

Jiang Yan closed the door.

"He was also the one who found the second body disposal site."

These words extinguished the fire that was burning half the room.

Old Qi looked up at Lu Yuan.

The kid in front of me had a chipped paint on his thermos and his reflective vest was loose and baggy, like it was borrowed from the city management auxiliary team.

Old Qi stubbed out his cigarette: "Do you have a contingency plan?"

Lu Yuan unscrewed the thermos and blew on it.

"no."

Cui Lei almost rushed over: "What were you doing in there if you weren't there?"

Lu Yuan took a sip of the goji berry water. "Give me the money."

There was a two-second silence in the monitoring room.

Jiang Yan pressed down on Cui Lei's shoulder. "Let him give it a try."

The thick door to the interrogation room was pushed open.

Lin Qinghui looked up and saw the person who came in, his eyebrows twitching slightly.

Lu Yuan pulled out a chair, sat down, and placed the thermos on the table.

"Dr. Lin."

Lin Qinghui glanced at the reflective vest that was askew on his chest, and then at the old thermos.

"Actors can now participate in criminal interrogations? Your bureau's procedural management is truly eye-opening."

He smiled.

"Mr. Lu, I've seen your movies. Your acting was good, but an interrogation isn't a movie set. If you're going to ask questions, please confirm your identity and authority first."

Lu Yuan screwed the lid back on.

"I don't need to memorize the laws; they're useless to me."

Lin Qinghui's smile froze on his face.

Lu Yuan crossed his arms and placed them on the table.

"Someone's paying me to grade this supposedly perfect handmade project of yours."

He looked at Lin Qinghui as if he were looking at a discarded internship report.

"Frankly, it's so rough it makes me sick."

Behind the one-way glass, Cui Lei opened his mouth.

Old Qi had a cigarette between his fingers, but forgot to light it.

Lin Qinghui narrowed his eyes. "The provocation tactic is very low-level."

"You're the lowly one."

"The Stryker System 7 oscillating saw was a good choice. The cutting speed was also quite stable. However, when retracting the blade, a non-uniform 0.02 mm abrupt change was left at the edge of the osteotomy surface."

Lin Qinghui's hand, which was resting on the table, stopped.

Lu Yuan continued.

"You think that's called a perfect anatomy? No, that's called shaky hands. Hands like mud, trying to act all ritualistic."

In the monitoring room, forensic doctor Lao Li approached the screen.

"0.02 millimeters... Have we enlarged our photos to that magnification?"

Xiao Zhou flipped through the computer: "Edge velocity restoration wasn't done."

Old Li cursed in a low voice, "Do it! Do it now!"

In the interrogation room, Lin Qinghui's breathing became erratic for the first time.

Lu Yuan could see it clearly.

He leaned forward, his reflective vest swaying under the light, looking ridiculously comical, yet no one could laugh.

"First, your chemical cleaning method is a joke."

Lin Qinghui looked up.

"You calculated that the sodium hypochlorite complex solution wouldn't corrode plastic bags, and you also calculated that hydrogen peroxide could damage the DNA double strand. But you overlooked one small thing."

Lu Yuan tapped the table with his fingertips.

"Electrostatic adsorption in the interlayer of the double-layer industrial moisture-proof bag."

Behind the one-way mirror, Old Li slammed his hand on the table. "Right!"

Everyone looked at him.

Old Li's voice was hoarse, "The double-layer membrane! We only cleaned the inner and outer surfaces, we didn't remove it! Static electricity attracts trace amounts of skin flakes, so the medicine can't penetrate!"

Forensic investigator Xiao Zhou picked up the evidence box and rushed out.

"I'm going to the lab!"

Cui Lei stood rooted to the spot, his back tingling. No one had thought of such a bizarre angle in three days.

In the interrogation room, Lin Qinghui's jawline tightened; he was still holding on.

"Just speculation."

"second."

Lu Yuan ignored his rebuttal.

"You spend three years planning for blind spots, turning your life into a clockwork routine. Checking in, access control, dry cleaning, even the label on a bottle of mineral water has to face outwards."

Lin Qinghui's eyelid twitched.

Lu Yuan said, "But you're stupid enough to always go to the same dry cleaner to get the linings used in the crimes removed."

Lin Qinghui raised his head.

This time, there was no more attempt to cover it up. "You're talking nonsense."

"Tetrachloroethylene in modern dry cleaning solutions can solidify trace amounts of porphyrin compounds from the blood into the fabric fibers. Luminol may not be bright, and conventional reagents may not be able to detect it, but high-performance liquid chromatography can extract it from deep within the fibers."

Lu Yuan paused.

"Your silk pajamas that you wipe with alcohol wipes every day are solid evidence."

Jiang Yan stood in front of the glass without saying a word.

She saw Lin Qinghui's fingers gripping the armrest of the interrogation chair.

His "perfection" was ripped apart in front of him.

Lu Yuan stood up.

The chair legs scraped against the ground, making a screeching sound.

Lin Qinghui instinctively leaned back.

Lu Yuan placed his hands on the table and looked down at him.

That street-smart air has been stripped away.

The thermos, the reflective vest, the loose shoelaces—they're all still there.

But the person sitting across the table is an ancient monster who stands at the top of the food chain, looking down on his prey.

"The stupidest point is the third one."

Lin Qinghui's Adam's apple bobbed.

Lu Yuan stared at him. "You think you can wash away the filth that's been ingrained in your bones since you were six years old by cutting others to pieces?"

Lin Qinghui's pupils constricted.

"Shut up."

Lu Yuan moved forward an inch.

"You can't wash it off."

"Shut up!"

"You are not a doctor, not a cleaner, not a judge. You are just that child shivering in the stench."

Lin Qinghui's shoulders began to tremble.

Every word Lu Yuan uttered resonated deep within him.

"Things that grow up in a garbage dump, even if they wear silk and are washed until their skin peels, are still garbage."

Lin Qinghui's face completely lost its color.

The next second, he clutched his head, curled up in the interrogation chair, and let out a broken scream.

"Stop talking!"

The two detectives in charge of the interrogation stood up.

Lin Qinghui slammed his head against the back of the chair, his voice rising to an uncontrollable level.

"It was me! I did it all!"

He was breathing heavily, his tears and sweat mingling together.

"The cotton mill, the power distribution room, the No. 3 culvert... and the old cold storage's underground drainage well... Enough! I admit it! I admit it all!"

No one moved in the monitoring room.

Old Qi remained in a half-standing position.

Cui Lei's hand was still on the doorknob, originally intending to go in and drag Lu Yuan out.

Now that hand is slowly being lowered.

A dozen veteran detectives looked at the high-IQ psychopath on the screen who had completely broken down, and then looked at the young man in the reflective vest in front of the table.

No one spoke.

Lin Qinghui's psychological fortress, built up over thirty years, was shattered by Lu Yuan's few words, which pierced through the very foundation.

In the interrogation room, Lu Yuan picked up his thermos again, his aura completely subdued.

He knocked on the one-way glass.

"Captain Jiang, the man has been identified."

Jiang Yan looked at Lu Yuan behind the glass and picked up the walkie-talkie.

"The recorder enters and takes a statement."