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

He wiped the sweat from his forehead, the beam of his flashlight swaying on the murky water: "We've been searching for three hours. Could it not even be in this ditch?" Yang Sen squatted on the bank, picking up a clump of plastic bag tangled with water plants with tweezers, and replied without looking up: "Captain Lu suspects the murderer dumped the body along the current. If we keep searching upstream, we'll definitely find it."

Their conversation was interrupted by a sudden crackling of the walkie-talkie. Zhang Kai's voice carried a hint of excitement: "DNA matching between the torso and severed limbs is successful, confirming they belong to the same person. However, there was no sludge in the victim's trachea, so it wasn't a drowning." Yang Lin gripped the walkie-talkie tightly: "We'll continue the search. Notify you immediately if we find anything." After putting down the equipment, he gazed at the winding ditch, the withered leaves floating on the surface resembling fragmented body parts. "Why do you think the killer dismembered the body? Wouldn't it have been better to just dump it directly?"

Yang Sen turned the metal detector to its highest sensitivity, and the machine emitted a regular "beep" sound: "Dismemberment usually has two possibilities: either it's for easier transportation, or it's to obfuscate identities." He kicked away the rubble at his feet. "But this killer used a chainsaw, and the cuts are so clean; he might be an expert." Just as he finished speaking, the detector suddenly emitted a piercing long beep, and the pointer swung wildly. The two men exchanged a glance and rushed towards the source of the sound.

It was a patch of reeds at the bend of the canal, the rotting roots intertwined in the water. Yang Lin stirred the water with his probe and suddenly touched a heavy object. He took a deep breath and, together with Yang Sen, pulled up the tangled weeds. A black plastic bag floated to the surface, the outline of a bulging spherical shape vaguely visible inside. "Careful!" Yang Sen put on gloves and slowly untied the bag. A strong stench of decay hit them—inside was the head of the dead they had been searching for.

“Contact Zhang Kai and prepare to receive the body parts.” Yang Lin’s voice trembled slightly as he raised his camera and took several photos. In the instant the flash went off, he noticed blood clots forming in the victim’s half-open eyes. “Subconjunctival hemorrhage, likely strangled.” Yang Sen used tweezers to part the victim’s tangled hair and felt a dent at the back of the head: “There are also blunt force injuries. This killer is ruthless; he attacked twice.”

The two carefully placed the head into the body bag. Yang Sen suddenly pointed to the mud on the bank: "Look at this, fresh tire tracks!" Two intersecting tire tracks were deeply embedded in the mud, extending towards the dirt road in the distance. "Check the surrounding surveillance footage and see which vehicles passed by in the last two days." Yang Lin squatted down to measure the distance between the tire tracks. "The tire width is 195mm, and the wheelbase is over 2.7 meters, so it looks like an SUV." He took out an evidence bag and scraped off the black debris stuck to the edge of the tire tracks. "Asphalt particles; there should be an asphalt road nearby."

On the way back, the walkie-talkie crackled to life again. Zhang Kai's voice was weary: "The head and torso match perfectly. The deceased's first upper molar shows obvious signs of decay and repair, made with amalgam, a material rarely seen nowadays." Yang Lin frowned in thought: "This suggests the deceased was older and likely not well-off. By the way, is there any clue about the lotus tattoo on his waist?"

"We're contacting the tattoo association, but this kind of design is too common, making the investigation very difficult." Zhang Kai paused. "We've also made an important discovery: the skin tissue extracted from the deceased's fingernails tested positive for machine oil, indicating he was likely a worker who was in prolonged contact with machinery." Yang Sen was quickly jotting down notes in his notebook when he suddenly looked up: "An abandoned factory! There's an abandoned factory not far from where we found the right hand! There must be clues there!"

As night deepened, the two investigators' lights swept across the rusty iron gate of the abandoned factory. Yang Lin tried to push the gate, but it wouldn't budge. "Go in through the side window." They climbed over the broken glass window, their flashlights illuminating the dusty workshop. Various tools were scattered on the floor, and a chainsaw in the corner was still stained with dark red dirt; its model perfectly matched the dismemberment cuts.

"Found it!" Yang Sen's voice echoed in the empty factory. He pointed to the employee handbook on the wall, the yellowed pages bearing the words "Safety Operation Procedures" in large print, with a date five years ago at the bottom. Yang Lin picked up the handbook and found a faded photograph tucked inside—the photograph showed several men in work clothes standing at the workshop entrance, one of whom had the edge of a lotus tattoo faintly visible on his waist.

"Send the photos to Zhang Kai immediately and compare them with the details of the victim's tattoos." Yang Lin's heart raced. "It seems we're not far from the truth." Outside the factory, the red and blue lights of police cars pierced the night as Lu Chuan led his team to the scene. Looking at the photos in his hand, his eyes sharpened: "Investigate the identities of these people, especially those who worked here five years ago. The murderer is very likely among them."

That evening, in the Criminal Investigation Division's office, the monotonous hum of the air conditioner mingled with the incessant tapping of keyboards. Wang Shuai stood before the whiteboard, emphatically circling the victim's features with a red marker, the ink spreading across the cold white surface: "Mechanical operation experience, amalgam dental fillings, lotus tattoo on the waist, age 45-50—screen based on these criteria. Remember, any detail could be a breakthrough."

Xiao Wu slumped in his swivel chair, twirling his ballpoint pen: "Captain Wang, with so many migrant workers in the city, including tens of thousands of mechanics alone, how long will it take to screen them all?" His cuffs were stained with coffee, and the 37th "insufficient similarity" message popped up on the computer screen. Old Zhang took off his reading glasses and vigorously wiped them with the corner of his shirt, the verdigris on the metal temples smearing onto the fabric: "What's even more problematic are these handwritten files. Records before 2020 were all entered manually, riddled with typos, some names even spelled with homophones."

Intern Xiao Chen stared at the blurry ID photo on the screen and suddenly exclaimed, "This photo is completely illegible! The system still insists I do a facial comparison; isn't this just messing with us?" Her voice trembled with tears, and her eyes were bloodshot. Da Liu was frantically restarting the crashed facial recognition system, his keyboard pounding deafeningly: "This damn system keeps breaking down every few days! We should have said we needed to replace the equipment! The leadership only talks about valuing technology; our funding application has been pending for six months!"

Wang Shuai walked over and patted Xiao Chen on the shoulder: "Mark the blurry photos in red; they'll be manually reviewed later. Hang in there, everyone. We can only move forward after we find the body." His phone suddenly vibrated; it was a new clue from Zhang Kai: the deceased had calluses on the web of his right hand from years of gripping the steering wheel. "Listen up!" Wang Shuai raised his voice, "Supplement the screening criteria, focusing on truck drivers and forklift operators!"

Old Zhang pulled out a stack of yellowed files, a dry leaf falling from between the pages. (End of Chapter)