Attending ex-girlfriend's wedding, arresting the groom's officer on the spot

Li Nana's neighbor provided a more crucial clue. "Around 5 PM on July 18th, I saw Zheng Baohai drive home in a black BYD," said Ms. Zhang, who was picking vegetables downstairs, the fibers of the green beans breaking between her fingers. "There was a rusty steel pipe in the back seat, about knee-length. He usually gets off work at 5 PM, but he came home half an hour early that day and even argued with Li Nana in the hallway, it seemed to be about 'money'." She suddenly slapped her thigh, and two green beans rolled out of her basket. "That's right! The red dress Li Nana wore that day was the same color as the woman's clothes seen near the abandoned parking lot in the surveillance footage!"

Zhang Hui immediately retrieved the surveillance footage from the resettlement housing community. At 5:23 PM on July 18th, Zheng Baohai's BYD drove out of the community, and Li Nana, in the passenger seat, was indeed wearing a red dress. The vehicle's GPS track showed that they drove west along the ring road, appearing at 5:47 PM on a side road near the building materials market, only 300 meters away from where Sun Qiang's Lavida last disappeared. "At 5:52 PM, the vehicle stopped in the woods by the roadside and didn't restart until 6:40 PM," Zhang Hui zoomed in on the surveillance screenshot, where two figures could be vaguely seen moving outside the car in the shadows of the woods. "This time was enough to commit the crime and move the body."

Sun Qiang's bank statements were laid out on Zhang Hui's desk. The 20,000 yuan he paid to Li Nana on June 28 was his earnings from a ride-hailing platform. "This money was the last payment for our divorce settlement," Sun Qiang's wife said, wiping away tears. She had a photo of the divorce agreement on her phone. "He said that once he paid this money, everything would be over and we could live a good life from now on." However, Li Nana's account statements showed that the money was transferred to Zheng Baohai's account on July 1 and then withdrawn that same day. Surveillance footage showed Zheng Baohai operating an ATM, his black plastic bag bulging.

During a visit to Li Nana's workplace, Zhang Hui found her colleague in the clothing store's warehouse. "Nana took half a day off on July 18th, saying she was going to the hospital," the shop assistant said, arranging dresses hanging on racks, perfume bottles reflecting shimmering light on the shelves. "But I saw her at the building materials market at 7 pm, arguing with a man on the roadside. The man was carrying a black bag; he looked like Zheng Baohai." She suddenly remembered something, "A few days ago, Nana asked me, 'How do you deal with the marks after hitting something with your car?' At the time, I thought she was joking, but now that I think about it..."

Zheng Baohai's renovation site was in a new residential complex in the east of the city. When Zhang Hui found him, he was squatting on the ground cutting tiles, the roar of the chainsaw making everyone's eardrums hurt. "I don't know Sun Qiang," Zheng Baohai said, his protective mask slipping down to his nose, sparks flying onto his work pants. "I was working at the construction site on July 18th, and there are attendance records." But the foreman's testimony was completely different: "He left around 7 pm that day, saying that a water pipe at home had burst and he was in a hurry to go back and fix it." The site's surveillance footage showed that Zheng Baohai was carrying a long, rectangular tool bag when he left, which matched the length of the steel pipe described by the neighbor.

Technicians made a new discovery in the trunk of Sun Qiang's Lavida: several long brown hairs were found stuck to the lining fabric, and their DNA profile matched Li Nana's perfectly. "The trunk lock showed signs of being pried open," Yang Lin said, shining a multi-band light on the lock cylinder. "The pins were misaligned by 18 degrees, a 90% match to the crowbar in Zheng Baohai's toolbox." There was a dent in the exhaust pipe heat shield under the car, and analysis of the metal residue showed rubber particles identical to those in Zheng Baohai's BYD tires. "The two cars were in a collision, likely on the afternoon of July 18th."

Li Nana's call logs show that she called Sun Qiang at 5:10 PM on July 18th, for a duration of 1 minute and 23 seconds. "This time coincides with Sun Qiang's arrival near the building materials market," Zhang Hui noted on the timeline. "It's highly likely that Li Nana lured Sun Qiang under the pretext of discussing business." After the call ended, Sun Qiang's cell phone signal disappeared near the building materials market, while Li Nana's phone moved towards the abandoned parking lot, perfectly coinciding with Zheng Baohai's vehicle trajectory.

When Zhang Hui interrogated Zheng Baohai again, the air conditioner in the interrogation room emitted an old hum. "What were you doing at the building materials market on the afternoon of July 18th?" He pushed the surveillance screenshot in front of him. Zheng Baohai's Adam's apple bobbed violently, his knuckles whitening from gripping the armrests of the interrogation chair. "I...I went to buy decorating materials," his voice trembled, his eyes glancing at the camera in the corner, "I argued with Nana because she thought I bought things that were too expensive." Zhang Hui suddenly threw out a DNA report, "The hair in Sun Qiang's car trunk belongs to Li Nana, how do you explain that?" These words struck Zheng Baohai like a hammer blow, his shoulders slumping instantly.

Faced with the evidence, Li Nana finally broke down, the interrogation room lights illuminating her tear-streaked face. "It was Zheng Baohai who suggested it," her voice hoarse as if sanded, the handcuffs scraping harshly against the table. "He said Sun Qiang would be useless after paying the compensation, so it would be better to get some money for self-defense. We arranged to meet Sun Qiang at the building materials market, saying we had something for him. While he was opening the car door, Zheng Baohai hit him on the head with a steel pipe..." She suddenly slammed her head against the table. "I'm so sorry to him, and even more sorry to the children..."

Meanwhile, in the other interrogation room, the incandescent light flickered suddenly, and Zheng Baohai's shadow twisted into a strange shape on the wall. Zhang Hui slammed the ride-hailing membership card he had found in Zheng Baohai's work pants pocket onto the table. The crisp sound of the plastic card hitting the table made Zheng Baohai flinch. "What's with this card?" Zhang Hui's finger jabbed heavily into the words "Sun Qiang" on the card, his knuckles turning white from the force. "Didn't you say you didn't know him?"

Zheng Baohai's Adam's apple bobbed violently beneath his collar, as if something hot was stuck in his throat. His eyes were fixed on the scratches on the table, and his voice was so soft it was almost inaudible: "Found...found it, in the construction site's garbage dump." As soon as he said it, he realized he had made a mistake—Sun Qiang's membership card still had fresh milk tea stains on it, and tests showed that the composition was exactly the same as the milk tea in Sun Qiang's stomach contents, so it couldn't possibly have been found in the garbage dump.

Zhang Hui suddenly stood up, the chains of the interrogation chair rattling loudly. He walked behind Zheng Baohai, placed his hands on the back of the chair, and breathed on Zheng Baohai's neck: "What were you doing in the woods at six o'clock on the afternoon of July 18th?" His voice suddenly rose, "The surveillance footage showed you and Li Nana carrying something into the van—it was Sun Qiang's body, wasn't it!" Zheng Baohai's shoulders trembled violently, sweat trickling down his temples and into his collar, forming small puddles at his collarbone. (End of Chapter)