Courtyard House: I, the eldest son of the Jia family, have returned from the battlefield.

Jia Dongming smiled too; the long-lost camaraderie dispelled the chill of the night and the tension of moments before.

He steadied his bicycle, his voice filled with emotion: "I've only been back a few days, but the organization took good care of me and put me up at the steel rolling mill."

He paused, then suddenly remembered something urgent and hurriedly asked, "Dapao, you transferred to the police force? Which station are you in charge of now?"

"He was recently transferred to Jiaodaokou Police Station as its director."

Wang Dapao answered readily, then looked him up and down. "What's wrong? Got into trouble? It's the middle of the night."

The smile on Jia Dongming's face gradually faded.

He glanced around at the few police officers standing quietly, lowered his voice, but spoke clearly: "Dapao, meeting you is a coincidence, and also a stroke of luck."

I'm facing a tricky situation... and I don't know who to confide in."

Seeing his serious expression, which didn't seem like a joke, Wang Dapao also straightened his face, waved for the comrades beside him to step back a little, and then moved closer himself: "Speak, what is it? Why are you beating around the bush with me?"

Jia Dongming took a deep breath of the cold night air, his voice lower but carrying a heavy weight: "Our factory... probably has a rat in it, and a big one at that."

Tonight, one of my men went through a lot of trouble to meet me privately and spilled some information—there are enemy spies hiding in the steel rolling mill, even in our security department.

Wang Dapao's pupils suddenly contracted, and the muscles on his face tensed: "Enemy agents? In your factory? Is the information confirmed?"

His tone was urgent, with a professional alertness.

"My subordinate swore on his life."

He mentioned someone, Chen Jianfei, the captain of the Second Security Brigade.

Jia Dongming spoke at a steady pace, but emphasized each word clearly, "In addition, there was a workplace injury in Workshop 2 last year. The person in charge of security for that area was Zhang Yi, who asked me out tonight."

He suspected that something was more complicated than it seemed.

Wang Dapao was silent for a few seconds, with only the faint rustling of the night wind through the corner of his clothes.

When he looked up again, the excitement of their reunion was gone from his eyes, replaced by a sharp, knife-like light: "Old Jia, this isn't the place to talk."

"Come on, let's go to the office. Tell me everything you know, from beginning to end."

As night deepened, Zhang Yi sat alone in the duty room under the dim light.

When the door was pushed open, he recognized Chen Jianfei from the Second Brigade.

Chen Jianfei didn't say much, but simply handed him a cigarette.

Zhang Yi took it, took a few puffs, and then felt dizzy. He soon slumped onto the table and lost consciousness.

The next morning, a piercing metallic clanging sound came from Workshop 2.

The machine involved in the accident was a specialized machine tool, which was usually operated by the factory's level eight fitter.

Unfortunately, the fitter wasn't there that day, and Jia Dongxu—Jia Dongming's younger brother—happened to be working next to that machine.

After the accident, Jia Dongxu never woke up again.

Upon hearing this, Wang Dapao suddenly remembered something and looked up at Jia Dongming: "Wait, Dongming, didn't you get separated from your family when you were little? Could it be... you found them?"

Jia Dongming nodded, his tone indifferent: "After reporting to the steel rolling mill, the factory arranged for me to live in the courtyard at No. 95 Luogu Lane."

To my surprise, my mother and brother's family lived there.

Wang Dapao smiled and said, "This is great news! You've been searching for so many years..."

"My father has been gone for a long time."

Jia Dongming interrupted him, his voice devoid of emotion, "My younger brother also passed away in that accident last year."

Now only the elderly and children are left at home.

Wang Dapao was silent for a moment, then reached out and patted Jia Dongming on the shoulder before asking, "And then what happened? What happened to Zhang Yi after he woke up?"

He said he felt dizzy the next day and couldn't remember how he fell asleep at all.

Jia Dongming continued, "After disassembling and inspecting the machine, Engineer Xue from the factory determined that someone had tampered with it, which caused the frequent malfunctions and ultimately resulted in a death."

"In the first place, an investigation team should be set up to thoroughly investigate this kind of accident."

But the factory's investigation was just a formality.

Chen Jianfei suppressed the fact that Zhang Yi was sleeping on duty.

As for Engineer Xue, he was transferred to another location two months later.

"Zhang Yi also told me that if I hadn't come to the steel rolling mill, the position of head of the security department should have belonged to Chen Jianfei."

I was blocking his way, so he wanted to get rid of me.

He asked Zhang Yi to help deliver a winter jacket to the special workshop—the place with the tightest security in the factory.

It was this request that aroused Zhang Yi's suspicion.

Jia Dongming paused, then lowered his voice: "Judging from these signs, I think there might be someone else behind Chen Jianfei."

Transferring an engineer is no small matter, and covering up an accident investigation requires even more cooperation from higher authorities.

I've just arrived at the factory and don't know who else in the security department works for him.

I was just wondering who to ask to take over the investigation when I ran into you on the street.

After listening, Wang Dapao's brows gradually furrowed.

His years of experience made him realize immediately that this was not a simple internal dispute.

The ability to mobilize engineers, cover up murders, and plant informants within the factory—the person behind this is far from simple.

He hesitated for a long time before slowly saying, "You did the right thing."

The security department should not be trusted.

If the information leaks, the other party will become alert.

Jia Dongming nodded: "That's what I'm most worried about too."

When Zhang Yi came out to see me tonight, he noticed that someone was watching him near his house.

It circled around several times before finally shaking off its tail.

Chen Jianfei asked Ming to take Dongxi to the special workshop during his evening shift—we don't have much time left.

Wang Dapao remained silent for a moment, the ash from his cigarette falling silently from his fingers.

He raised his eyes and looked calmly at Jia Dongming: "Dongming, the only person we can confirm right now is Chen Jianfei, the captain of your security department's second brigade."

Whether his men are good or bad is still unclear.

He stubbed out his cigarette and lowered his voice even further, "The station is short-staffed, I'll go to the branch office to request reinforcements."

The steel rolling mill is a cesspool that must be thoroughly investigated.

Jia Dongming nodded emphatically, his fist clenching silently: "I'll listen to you."

"If the factory needs anything from me, just let me know."

"Chen Jianfei will make his move later; he must have met with his accomplices beforehand."

Wang Dapao spoke faster, "Give me Chen Jianfei and Zhang Yi's addresses, and I'll have people keep a close eye on them."

"Chen Jianfei lived in the courtyard at No. 37 Mao'er Hutong, in the winter wing of the backyard."

His wife died three years ago, leaving no children.

Jia Dongming replied almost without hesitation, "Zhang Yi lives at No. 29 Dahutong, Qianmen Street, in a two-courtyard house."

He paused, then added, "When Zhang Yi came to see me, he said he was being followed. I reckon the tail hasn't left yet."

Wang Dapao turned his head to the side: "Little Xu, got it?"

The young policeman's pen scratched across the paper, making a soft rustling sound: "Chief, not a single word is missing."

"There's no time to lose, I'll head to the branch office right away."

Wang Dapao grabbed his hat, patted Jia Dongming on the shoulder before leaving, and said, "Once this case is closed, we two brothers have to have a good drink together."

A bitter smile appeared on Jia Dongming's lips: "It's my turn to toast you."

You've been a great help this time.

"Old comrade, let's not talk about these things."

Wang Dapao waved his hand, and his figure quickly disappeared into the thick night outside the door.

As Jia Dongming pushed his bicycle away, the light from a cigarette butt seemed to dim slightly under the shadow of the locust tree at the alley entrance.

At the same time, in a deep, dark basement.

When Chen Jian pushed the door open and came in, the dim light bulb flickered.

The middle-aged man sitting behind the wooden table raised his eyelids, his voice cold and hard: "Tian Chuan, you're too late."

Chen Jianfei immediately bowed and said respectfully, "Colonel Koizumi encountered a police checkpoint on the way and had to take a detour."

"How's the plan going?"

"The tunnel is complete, and Dongxi has been buried properly."

A ruthless glint flashed in Chen Jianfei's eyes. "Mingtian, I'll have someone send a fake to Zhang Yi."

When he was on night shift, he transferred two security guards from his group.

As long as he brings Dongxi into the special workshop—

He cuts with his palm down, "and the explosives buried underneath will detonate."

Zhang Yi is a ready-made scapegoat.

Colonel Koizumi tapped his knuckles on the table: "Tagawa, don't be too optimistic."

The reason that incident was covered up last year was because Lin Zhendong didn't interfere.

"Now that Jia Dongming is in that position, if he personally investigates, the tunnel cannot be kept secret."

Chen Jianfei's face revealed a sinister smile that he had already planned: "Deputy Factory Director Zhang, once the workshop is blown up, you can submit a report to the higher-ups saying that Jia Dongming neglected his duties and was incompetent."

"Once he's removed, who will investigate? You can suggest I take over the investigation, and the traces of the tunnels... will naturally be wiped clean."

It was 10 p.m. at the Dongcheng District Public Security Bureau.

The light in the director's office was still on.

After Wang Dapao finished his report, the middle-aged man behind the desk took a brown paper bag from the drawer and pushed it in front of him.

"Take a look."

The director's voice carried the calm and collected tone of someone who had been through many battles.

Wang Dapao pulled out the files inside, flipped through only a few pages, and his pupils suddenly contracted.

He raised his face, his Adam's apple bobbing: "Director...you've been eyeing the steel rolling mill for a while now?"

"The steel mill reported the 'accidental' death last year as an equipment malfunction."

The director pointed to the case file, "But we received an anonymous letter saying that the machine was deliberately sabotaged."

The one who died was the apprentice; the one who truly deserved to die was his master—the factory's level eight fitter.

The only sounds in the room were the soft rustling of paper and the distant, unfathomable sound of the wind outside the window.

The value of an eighth-grade fitter in a steel rolling mill is self-evident.

The fact that such a serious accident was so easily suppressed suggests that the enemy hiding in the factory was definitely not a simple person.

After listening to the middle-aged man's account, Wang Dapao recalled the message from Jia Dongming and said in a deep voice, "Director, the fitter who took the blame is the younger brother of my sworn brother."

This time, no matter what, I have to find those 'rats' who are burrowing holes in the steel mill and get justice for my brother.

The next morning around 7 a.m., Jia Dongming dropped his child off and, as usual, rode his bicycle to the security department compound.

Good morning, Section Chief!

"Section Chief, you're here so early today?"

"Good morning, Section Chief!"

After parking his car and entering the building, he was greeted by the staff members he encountered along the way.

As Jia Dongming responded with a smile, he glanced at each face out of the corner of his eye—he didn't know if any of these people were Chen Jianfei's accomplices, so he could only remain silent for the moment.

Once inside the office, he sat down at his desk, pulled out a thick stack of files, and quickly found Chen Jianfei's file.

The resume clearly states: Chen Jianfei, native of Xinjing City, joined the Anti-Japanese United Army at the age of sixteen.

After the Japanese surrendered, he followed the army south and participated in the War of Liberation. He was discharged due to injury and resettled in Beijing, becoming an ordinary security officer at the Hongxing Steel Rolling Mill.

The paper appears clean, yet something strange is evident everywhere.

Xinjing was a Japanese-occupied area at the time, and the archives only mention the place of birth, with no information about parents or relatives.

According to the resettlement policy at the time, people whose place of origin was Xinjing (Beijing) should have returned to their place of origin after being discharged from the army. Why did he stay in Beijing? Looking at his marital status, Chen Jianfei had a brief marriage, and he has been single ever since his wife passed away.

Jia Dongming looked at the file several times, then gently placed it on the table, his fingers unconsciously tapping the surface.

"Xinjing...there were many institutions and schools there that were trained by the Japanese invaders back then."

He muttered to himself, "If Chen Jianfei is really a suspect, then he is either a descendant of Japanese people or a trained undercover agent."

"But if he were really a trained spy, he wouldn't have designed such a crude accident—unless, that fitter named Zhang Yi was just a pawn that Chen Jianfei used to cover up his true intentions."

Thinking about the importance of the special workshop, Jia Dongming stood up and decided to go to the site in person to take a look.

To avoid alerting the enemy, he first went into the logistics department's office and called out, "Comrade Guoping, are you free now?"

Zhang Guoping immediately stood up from his seat: "Section Chief, I'm free. Please give me your instructions."

"I'm going to take a walk around the factory area. If you're not busy, would you like to come with me?"