The crackdown on organized crime began with the arrest of the mother-in-law.

Chapter 1333 Investigating Liu Mei

Meanwhile, Lin Xiao in the forensic lab made a new discovery. She extracted a long, brown female hair from the collar of Ma Jianguo's jacket; the hair was dry and completely different from Ma Jianguo's. "Professor Zhang, this hair isn't Ma Jianguo's; it's very likely left by that woman!"

Zhang Lin immediately conducted a DNA test on the hair. Although the results weren't back yet, he knew that this strand of hair could very well become the key evidence in identifying Liu Mei. The operating lights on the autopsy table remained on, just like the belief in the hearts of the criminal investigators: no matter how complex the case, no matter how cunning the murderer, they could piece together the complete truth from every tiny clue and give the deceased a just explanation.

To uncover the entanglement between Ma Jianguo and Liu Mei, we must trace back to the buried past three years ago. According to the business records and interview transcripts retrieved by the team, Liu Mei's "Honest Machinery Repair Shop" opened in 2018. Initially, it was just a small stall of less than ten square meters, barely making ends meet by repairing small household appliances. It wasn't until 2020, through an acquaintance, that she met Ma Jianguo and truly entered the field of machinery repair. Ma Jianguo had worked in a large machinery factory for twenty years and was well-known in the industry for his repair skills. However, his straightforward personality and inflexibility offended the factory's leaders, leading to his demotion from a permanent employee to a temporary worker.

"Back then, Liu Mei visited Ma Jianguo three times to ask him to help out, promising a monthly salary of 8,000 yuan, plus room and board," recalled Mr. Wang, Ma Jianguo's former colleague who introduced him to the job. "Ma Jianguo had just gotten divorced and needed money urgently for his son's college tuition, so he agreed. But after working for half a year, Liu Mei started to delay paying his wages, saying that the store was having cash flow problems."

A 2021 wage slip that Xiao Zhou found during his investigation corroborated Mr. Wang's account. The slip stated, "I owe Ma Jianguo 10 yuan in wages, to be paid in full before October 2021," and was signed and fingerprinted by Liu Mei. However, according to Ma Jianguo's sister, Ma Jianlan, Liu Mei never paid off the debt before Ma Jianguo disappeared. "My brother went to the shop every day to collect the debt, and Liu Mei always cried poverty, saying her husband had gambled and owed high-interest loans, and she simply couldn't afford it," Ma Jianlan said, her eyes red. "Once, the two of them argued in the shop, and Liu Mei pointed her finger at my brother's nose and called him heartless, saying that if it weren't for her, my brother wouldn't even have a job."

The real conflict erupted in September 2021. Liu Mei had received a large order—to repair three large reactors for a local chemical plant, priced at 120,000 yuan. She approached Ma Jianguo, promising him a 30,000 yuan commission upon completion and giving him full responsibility for the repairs. "Those three reactors were imported equipment, and parts were hard to find. To meet the deadline, my brother lived in the shop for a month straight, sleeping only four hours a day," Ma Jianlan said, showing a photo Ma Jianguo had taken at the time. In the photo, Ma Jianguo was wearing oil-stained work clothes, his eyes bloodshot, but with a smile on his face. "He told me that with the commission, he could pay for his nephew's tuition and save some money to open his own small shop."

But no one expected that Liu Mei would change her mind after the repair work was completed. She told Ma Jianguo that the chemical plant had only paid 80,000 yuan for the project, citing "substandard repair quality," so her commission would only be 10,000 yuan. Ma Jianguo, of course, didn't believe it and went to the chemical plant to verify, only to find that the 120,000 yuan project fee had already been paid in full. "When my brother came back, he was trembling with anger. He took the chemical plant's payment voucher to confront Liu Mei," said Master Wang. "The two of them argued fiercely in the shop. Liu Mei admitted that she had embezzled the project funds and said that Ma Jianguo was just an employee and had no right to tell her how to use the money."

What angered Ma Jianguo even more was that he discovered Liu Mei had used the money not only to pay off her husband's high-interest loans, but also to buy a gold necklace worth 8,000 yuan. "My brother said he was going to report her to the labor department, and Liu Mei threatened him, saying that if he dared to report her, she would have someone deal with him," Ma Jianlan recalled. "At that time, my brother had already received anonymous threatening letters, saying that if he forced Liu Mei to repay the money again, he would never see the sun rise the next day."

October 15, 2021, was the last time Ma Jianguo appeared in public. That day, he was wearing dark blue overalls, carrying a tool bag, and told Ma Jianlan that he was going to "settle things" with Liu Mei. "He said if Liu Mei was willing to pay back her commissions and owed wages, he would not pursue the matter further; if she was not, he would take the evidence to the police," Ma Jianlan said, choking back tears. "I never imagined that this would be the last time my brother and I would see each other."

After Ma Jianguo disappeared, Ma Jianlan reported it to the police, but because no signs of a struggle or a missing person scene were found, the case was classified as "voluntary runaway." It wasn't until three years later, when Ma Jianguo's body was found in the basement of the Northern Building, that this long-dormant disappearance case resurfaced. "I knew my brother wouldn't disappear for no reason; Liu Mei must have killed him," Ma Jianlan said, grabbing Xiao Zhou's hand excitedly. "Officer, you must avenge my brother!"

With these clues in mind, Xiao Zhou arrived at Liu Mei's repair shop early the next morning. The shop had expanded, with a brand-new SUV parked outside and two young mechanics working inside. Liu Mei was dressed in a well-fitting dress and had exquisite makeup on, a stark contrast to the "haggard boss lady" image described during the previous visit.

“Ma Jianguo? I’d forgotten about him a long time ago.” When Xiao Zhou mentioned Ma Jianguo’s name, Liu Mei’s hand holding the teacup paused for a moment, then she regained her composure. “He resigned and left three years ago, saying he was going to work in the south. Why are you suddenly asking about him?”

"He's dead. He died in the basement of the Northern Building. The time of death was around 10 p.m. the night before last." Xiao Zhou stared into Liu Mei's eyes. "We found out that you had a financial dispute with him. Before he disappeared, he repeatedly asked you for the back wages and commissions he owed, is that right?"

Liu Mei's face turned pale instantly. She put down her teacup, took out a cigarette case from the drawer, lit a cigarette and started smoking: "Yes, I owed him money, but I have already paid it back." She took out a receipt from the safe, "This is a receipt he wrote on October 14, 2021, for 32,000 yuan in salary and 30,000 yuan in commission, a total of 62,000 yuan, and he received it all."

Xiao Zhou took the receipt and examined it carefully. The handwriting on the receipt did indeed match Ma Jianguo's handwriting, and the date was clearly visible. But he immediately noticed something suspicious: "Ma Jianguo's sister said that you had an argument with him in the store on October 15, 2021, but this receipt is dated October 14. How do you explain that?"

Liu Mei's eyes flickered: "He went back on his word, saying that I forced him to write the receipt, and then he came to ask me for money again. I had no choice but to give him another 10,000 yuan before he left."