Lu Chenzhou pressed the half-smoked cigarette against the rusted lid of a trash can outside the medical supply store. The butt fell into the half-full, murky water with a faint sizzle. He turned and, without another glance at the gray sedan parked across the street, merged into the morning rush hour crowd. The flow of people was murky, carrying with it the steam from steamed bun stalls and the sticky smell of exhaust fumes that clung to skin. His pace was neither hurried nor slow, his gaze sweeping over the reflections in the shop windows—a black jacket, a dark baseball cap, a blurred silhouette no different from the surrounding office workers. In the reflection, the gray sedan hadn't moved, like a stone sunk to the riverbed. He took a right at the first intersection and ducked into the subway station. On the descending escalator, he sidestepped to let a woman holding a child pass, his fingertips unconsciously rubbing the rough edge of the old cigarette pack in his pocket. The pack was light, but the secret hidden within pressed heavily on his gut. Lin Xiuyun was still alive, hidden somewhere in a room in Kangning Building of Ci'an Nursing Home. And someone was circling above the nursing home like a vulture, also circling behind him. The subway car was packed like a sardine can. The smell of sweat, cheap perfume, and the greasy aroma of leek-stuffed pastries swirled together in the stifling heat. Lu Chenzhou leaned against the door, observing the people behind him through the glass reflection. A young man with earphones, a middle-aged woman constantly checking her watch, an old lady dozing off with a vegetable basket. No repeated faces. The person from the gray sedan might not have followed him down, or they might have switched. He got off at the third stop, didn't exit the station, but instead boarded a train on another line going the opposite direction. The carriage was much emptier, the air conditioning cranked up high, raising goosebumps on the back of his neck. He sat down, took out an encrypted tablet from his backpack. The screen lit up with an eerie blue light. His fingers swiped, calling up not a map of the nursing home, but another file—a supplementary appraisal opinion from ten years ago, from the Handwriting Identification Office of the Municipal Bureau's Technical Division, regarding the "authenticity of signatures on Secretary Sun Henian's reimbursement documents." Issuer: Zhou Zhengping. In the file photo, Zhou Zhengping was wearing an old-style police uniform shirt, smiling stiffly at the camera, deep wrinkles gathered at the corners of his eyes. It was his last work photo before retirement. After retiring, this man had evaporated like a drop of water. Official records showed he had returned to his hometown in the neighboring province, but the fragmented information Shen Qinghuan provided pointed to another possibility: he hadn't gone far. His daughter, Zhou Xiaowen, had undergone a major surgery at the old cotton mill workers' hospital in the western part of the city ten years ago, requiring long-term follow-up checks afterward. A father, a father full of fear wanting to live under an assumed name, where would he most likely choose? An old, dilapidated community, not far from his daughter's former hospital, with low rent, high resident turnover, and indifferent neighborly relations. Lu Chenzhou turned off the tablet. Gears meshed in his mind, emitting silent, crisp clicks. The seed had to break through the concrete today. He couldn't go to Ci'an Nursing Home to be a live target anymore; he needed to first get the key that could pry open that door—Zhou Zhengping's testimony. About how that appraisal opinion from back then was "handled ambiguously," about the hand manipulating the handwriting from behind the curtain. He got off at a large commercial complex station and cut through the mall. The first-floor cosmetics counters emitted a cloyingly sweet fragrance, the lights glaringly bright. He entered a fire escape; the heavy door closed behind him, shutting out the noise. Only the green glow of the emergency exit sign illuminated the stairwell. His footsteps echoed on the concrete steps, eerily clear. He descended to the underground second-level parking lot, exited from another door, and circled to the back of the building. A row of shared bicycles was parked there. He scanned a code to unlock one, mounted it, and the wheels rolled over the damp surface of the back alley. Moss crept along the base of the walls; the air carried a faint musty smell and the sour, rotten odor from a distant garbage station. The bicycle chain clicked softly as it carried him into the intricate, capillary-like network of backstreets and alleys of the city. Maps were useless here; surveillance cameras were sparse. He slipped into the shadows like a fish. Two hours later, he stood on the outskirts of the “Who do you think they’ll be curious about, standing at the door of the west unit on the top floor?” A few seconds of dead silence. The breathing behind the door was heavy, like a broken bellows. Finally, the door hinge let out a groan, slowly swinging inward. The light inside was dim. The curtains were drawn tight, with only a single low-wattage energy-saving bulb hanging in the center of the living room, casting a cold, bluish-white light that held no warmth. The air was stale, mixed with the musty smell of old books, the astringent odor of cheap tea, and that lingering, decaying scent unique to elderly people living alone. The living room was small, crammed with books and storage boxes, leaving almost no space to move. The balcony, as expected, was lined with potted plants, but most of them were wilted and drooping, their leaves yellowing. Only a few pots of cacti still clung to a faint hint of green. Zhou Zhengping stood behind the door, thin as a bamboo pole, wearing a faded blue work uniform. His fingers dug tightly into the doorframe. He was in his sixties but looked older, with sunken eyes, prominent cheekbones, and every wrinkle on his face etched with fear. His gaze swept quickly over Lu Chenzhou’s face, then darted away, unable to meet his eyes. “You… who are you?” The voice was hoarse, trembling. Lu Chenzhou closed the door behind him but didn’t lock it. He stood in the narrow space of the entryway, maintaining a distance of over a meter from Zhou Zhengping. “Lu Chenzhou. Formerly with the Criminal Investigation Division. Not anymore.” He paused. “I’m here to ask about that appraisal report.” Zhou Zhengping’s body visibly swayed. He took half a step back, his spine bumping against a bookcase piled high with volumes, making a faint sound. “I don’t know what you’re talking about. What appraisal report… I’ve been retired for many years. Things from back then… I can’t remember clearly.” “Can’t remember clearly.” Lu Chenzhou repeated the words, his tone not mocking, merely stating. He took a transparent document pouch from his inner jacket pocket, containing photocopies of several A4 pages. He pulled out one page and held it up to the light. “This is a copy of the original appraisal report filed in the case records from back then. The conclusion was ‘tending to confirm identical handwriting.’ The signature block bears your name.” Zhou Zhengping’s gaze was fixed on that page, his pupils contracting. “But here,” Lu Chenzhou flipped to the next page, a copy of another document with a slightly different format, on older-looking paper, “this is the draft found in the original examination records kept internally by the Technical Department. The conclusion is ‘significant differences exist, conditions for identity confirmation not met.’ The signature block,” he tapped the spot with his fingertip, “also bears your name.” He held the two pages side by side, letting Zhou Zhengping see them clearly. “Same evidence, same sample, same appraiser. Two documents with opposite conclusions, yet the handwriting comes from the same hand.” He set down the copies, his gaze falling on Zhou Zhengping’s violently trembling fingers. “Engineer Zhou, which one did you actually write back then?” Zhou Zhengping’s lips quivered, his face ashen. He shook his head violently, the words squeezed from his throat: “Fake… it’s all fake! You forged it! You’re trying to harm me!” Lu Chenzhou squatted down, meeting the other man at eye level, softening his tone, yet each word remained clear and forceful. "They used your daughter Zhou Xiaowen to threaten you. It was like that ten years ago, and it might still be the case now. But have you ever considered why, ten years later, I can still come knocking at your door? Why haven't they let you go? Because the thing you handled back then is a key. A key that can open a door can also lock a group of people inside. If you don't speak, this key will forever hang over you and your daughter's heads. If you speak," he paused, "I can find a way to snatch this key from their hands. At the very least, to prevent your daughter from being used as a bargaining chip again." “No! No one!” Zhou Zhengping was almost shouting, but the volume was suppressed, carrying a near-breaking-point tension. “It was me… I myself, during a later review, felt… felt the initial judgment was wrong…” “The draft date is September 3rd. The final version date is September 5th.” Lu Chenzhou interrupted him. “Only one day apart. What kind of ‘review’ could make a veteran technician with thirty years of handwriting appraisal experience turn ‘significant differences’ into ‘tending toward identical’ within twenty-four hours?” He took half a step forward, closing the distance. The cold, bluish-white light from the energy-saving bulb shone down from The room sank into a thick, almost suffocating silence. Under the pallid glow of the energy-saving bulb, dust motes drifted slowly. Zhou Zhengping leaned against the cold wall, his chest heaving violently, each inhalation a rasp like a torn bellows. He looked at Lu Chenzhou, his eyes churning with fear, shock, and a trace of guilt buried by time but abruptly unearthed now. Lu Chenzhou did not press him immediately. He stood where he was, his sharp gaze sweeping over the living room of less than twenty square meters. Stacks of old newspapers and books reaching the ceiling, a worn, peeling sofa, a few half-dead potted plants on the windowsill. The remaining years of a defeated old technician, all compressed into this dim, confined space. The stale smell of old paper and medicine in the air mixed with the near-despairing aura of decay emanating from the old man. "Water," Zhou Zhengping suddenly said, his voice dry as sandpaper. He pointed to an old-fashioned thermos in the corner. Lu Chenzhou walked over, picked up an enamel mug printed with faded red characters beside it, and poured half a cup of lukewarm water. The water was tepid, carrying the distinctive smell of a thermos rubber stopper. He handed the cup over. Zhou Zhengping took it, his hands trembling so violently that water sloshed out, dampening his faded, washed-out cuffs. He lowered his head and gulped several mouthfuls, then choked, coughing until his face turned red and tears were forced out. Only when his breathing had somewhat calmed did Lu Chenzhou speak, his voice gentler than before, yet each word still clear and heavy, as if stating an unchangeable fact. "Engineer Zhou, we don't have much time. My finding you means others might find you too. What happened back then, you and I both know, that wasn't the end." Zhou Zhengping clutched the enamel mug, his knuckles white. He no longer looked at Lu Chenzhou, but stared at the slightly rippling water surface in the cup. "...It was Shen Qinghuan." He uttered the name, his voice so soft it was almost inaudible, yet it seemed to drain all his strength. "Back then, the message was passed through a middleman called 'Old K.' But the final confirmation, the instruction demanding that the 'tending towards identical' conclusion be completely obfuscated into 'doubtful'... that was a phone call from Shen Qinghuan himself." He lifted his head, his eyes sunken, filled with ten years of accumulated exhaustion and fear. "I can't forget the voice. Very young, tone very polite, even carried a hint of a laugh, but the meaning in the words... left no room for maneuver. He said, 'Engineer Zhou, technology must serve the greater situation. Handwriting analysis is a science, but reports are written by people. People must understand boundaries.'" Lu Chenzhou's heart sank heavily. *Shen Qinghuan.* The only son of Shen Moqing, who had just entered the group back then, nominally just an assistant. The missing key piece of the blueprint snapped perfectly into place now. Not Shen Moqing himself, but his carefully groomed heir, already using such methods to 'handle' trouble ten years ago. What did that mean? It meant the Shen family's reach was deeper, earlier than anticipated. It also meant Zhou Zhengping might know more than just this one thing. "Besides Sun Henian's expense report, was there anything else?" Lu Chenzhou asked, leaning forward slightly, creating a silent pressure. "Similar appraisals where you needed to 'understand boundaries'?" Zhou Zhengping's eyes flickered, revealing a deeper fear. His lips moved, but in the end, he just shook his head, buried his face in his hands, and his shoulders slumped. "...No. Just that one time. Just that one time was enough to cost me my whole life." His voice leaked through his fingers, choked with sobs. "My wife... my daughter... they know nothing. I hide here, like a rat... for ten years..." Emotion poured out, no longer just pure fear, mingled with heavy remorse and self-loathing. Lu Chenzhou watched him. This old engineer once known for his rigor and inflexibility in the technical department was now curled up on the shabby sofa like a patient whose backbone had been removed. Empathy? A little. But more so, it was a cold assessment. Zhou Zhengping was a witness, a key source of information, and also the most fragile link. Zhou Zhengping shook his head violently, clutching his head with both hands, his body sliding down the wall to sit hunched in a ball. "I don't know... I don't know anything... Let me go... I'm retired... My daughter Xia Lu Chenzhou crouched down, meeting his gaze at eye level, his tone softening but each word still clear and forceful. "They used your daughter Zhou Xiaowen to threaten you. That was the case ten years ago, and it might still be the case now. But have you ever considered why, ten years later, I can still find my way to your door? Why haven't they let you go? Because what you handled back then is a key. A key that can open a door can also lock up a group of people. If you don't speak, this key will forever hang over you and your daughter's head. Only if you tell me," he paused, "can I figure out a way to snatch this key from their hands. At the very least, to stop your daughter from being used as a bargaining chip." "Snatch it?" Zhou Zhengping looked up, his turbid eyes filled with despair and a faint, almost unbelievable glimmer of hope. "How can you snatch it? They... they are..." "Who are they?" Lu Chenzhou pressed, his heart pounding heavily in his chest. The room seemed to shrink, the walls silently pressing in. He had to hear that name. Zhou Zhengping's lips trembled, his gaze darting away. Finally, as if all his strength had drained away, his voice dropped to a near-whisper. "They didn't contact me directly... There was a middleman, used to work for an association under the Justice Bureau, surname Dong... He brought the message, and... and a sum of money, said it was 'hardship compensation.' But between the lines, he mentioned... mentioned that Mr. Shen valued this matter highly, that there must be no slip-ups. Mr. Shen has a Mr. Gu by his side, responsible for handling... handling these 'technical details.'" He suddenly grabbed Lu Chenzhou's arm, his nails digging into the fabric. "It's Mr. Gu! Shen Moqing's legal advisor, Gu Zhixing! The message came from him! The money... the money was probably arranged by him too! That's really all I know! Back then, during the handwriting analysis... the pressure was immense. Secretary Sun was pushing, and there were hints from above..." Gu Zhixing. The name landed like a cold pebble dropped into still water. The corner of Lu Chenzhou's left eye twitched almost imperceptibly. The blueprint took physical form; the suspect shifted from the vague "Shen Moqing's confidant" to the specific "Gu Zhixing." An old debt was partially settled. But simultaneously, a greater chill crawled up his spine. Gu Zhixing knew about Zhou Zhengping. He knew ten years ago. And now? He helped the limp Zhou Zhengping up, supporting him to sit on the old sofa, then got up and went to the kitchen to pour a glass of warm water. The plastic cup was thin, the warmth seeping through negligible. He placed the water into Zhou Zhengping's trembling hands, then leaned against the greasy kitchen doorframe, briefly closing his eyes. Weariness washed over him like a tide, his temples throbbing. But he couldn't stop. "You can't stay here," Lu Chenzhou opened his eyes, his voice regaining its usual calm. "The commotion we just made might have drawn the neighbors' attention. And since Gu Zhixing knows your value, he might have been keeping an eye on you, or has ways to find you. You need to relocate immediately." Zhou Zhengping held the cup, staring vacantly ahead, as if not yet recovered from the massive emotional release and fear. "Relocate? Where to? My daughter Xiaowen... my daughter is still studying out of town..." "Regarding your daughter, I'll find a way to warn her to be careful. But right now, the most important thing is to get you to a safer place." Lu Chenzhou quickly thought of the backup safe houses, several locations provided by Fang Mu flashing through his mind. "Pack essentials: ID card, a small amount of cash. Don't bring anything else. We..." His words cut off abruptly. A sharp, old-fashioned cell phone ringtone exploded without warning in the deathly silent room. The sound came from the old flip phone Zhou Zhengping had left on the small coffee table. The screen emitted an eerie green glow in the dim light. Zhou Zhengping froze completely. The cup slipped from his hand, crashing to the floor, water splashing everywhere. He stared at the phone as if it were a venomous snake, his face instantly turning from ashen to deathly gray. Lu Chenzhou's heart sank. Quicksand was pulling him down. He made a silencing gesture, his eyes sharp. Trembling, Zhou Zhengping extended his bony hand, picked up the phone in slow motion, pressed the answer button, and held it to his ear. "Hello...?" The "Dad..." His daughter Zhou Xiaowen's voice came through the receiver, choked with sobs, fragmented. "They... they're at my school gate... they told me to tell you... to make you... make the person who came to see you... not leave... wait for them..." "Xiaowen! Xiaowen, what's wrong! Who are you! Let go of my daughter!" Zhou Zhengping roared into the phone, his voice cracking apart. The call was brutally cut off, leaving only a string of busy tones. Zhou Zhengping remained frozen in place, holding the phone to his ear. A few seconds later, the phone slipped from his hand and clattered to the floor. He whipped around to face Lu Chenzhou, his face streaked with tears and snot, a mixture of boundless terror and utter despair. "They've taken my daughter Xiaowen! They've taken my daughter! They told me... told me to keep you here... wait for them to come! What do I do... what can I do!" He wailed, then desperately clamped a hand over his mouth, emitting muffled sobs. Lu Chenzhou was no longer where he had been. The moment Zhou Zhengping answered the phone, he had darted to the window like a leopard, his movements swift and silent. He lifted a corner of the heavy curtain, just a sliver, and peered outside. Below, on the previously empty community road, two black SUVs had appeared out of nowhere. Their engines were still running, faint white smoke curling from the exhaust pipes. Doors opened, and several men in dark casual clothes, moving with practiced efficiency, quickly disembarked and fanned out silently. Two headed straight for the entrance to this unit, while the others swiftly circled to the back and sides of the building, blocking all possible exits. One of them looked up, his gaze seemingly casual as it swept over the windows of this building, cold and precise. An encirclement. Completed in an instant. Lu Chenzhou let the curtain fall, plunging the room back into gloom. The cold beams of the car headlights seemed to linger on his retinas, mingling with the sudden metallic taste flooding his mouth. He turned and looked at Zhou Zhengping, who had nearly collapsed on the sofa, completely broken. The enemy wasn't possibly coming; they were already here. Either Gu Zhixing, or someone sent by Gu Zhixing, or... another, more unknown force. They had used Zhou Zhengping's daughter, Zhou Xiaowen, as a precise shackle, severing any room for maneuvering. Time. Possibly only a few minutes, maybe less. Lu Chenzhou strode back to Zhou Zhengping, crouched down, grabbed his trembling shoulders with both hands, and forced him to meet his eyes. His gaze was like a blade, his voice lowered to a whisper, yet carrying undeniable decisiveness. "Listen to me!" He cut off Zhou Zhengping's meaningless sobs. "They took your daughter because you spoke to me. Right now, the only chance to save her is for us to get out of here first! Only if we get out alive do we have leverage! Your daughter is still a hostage now. If we die or are captured, she loses her value. Understand?" Zhou Zhengping's eyes were unfocused, as if he couldn't comprehend. Lu Chenzhou increased the pressure of his grip, almost crushing the man's bones. "The back balcony! Your back balcony—is there any way down to the platform of the next building? Or leading somewhere? Think! Fast!" Zhou Zhengping was cowed by his gaze and strength, his chaotic thoughts forced to work. He pointed a trembling finger toward the other side of the living room. "B-back... back balcony... full of junk... outside... outside is the roof of the next building... but there's a... a lane in between, it's far... below... it's the sixth floor... impossible... impossible..." "How far?" Lu Chenzhou pressed. "At... at least two meters... maybe more..." Zhou Zhengping slumped back, utterly hopeless. "Can't jump it... dead end..." Two meters. The height of six stories. Concrete ground below. At the same moment, heavy, rhythmic pounding sounds came from the direction of the security door. *Thud!* The doorframe shook, dust sifting down. *Thud!* Another, heavier blow. The old lock groaned under the strain. *Thud!* Lu Chenzhou released Zhou Zhengping and shot to his feet. His eyes swept rapidly over the room that had become a cage, over the broken old man, over the shattered glass on the floor and the old phone still blinking with a green light, finally fixing on the shabby wooden door leading to the narrow back balcony, half-blocked by clutter. If there's no way out, create one. He hauled the limp, unresisting Zhou Zhengping up from the The banging on the door stopped. Immediately after came the sound of a key being inserted into the lock and turned roughly. They had a key, or they were using lockpicking tools. The sound of the lock turning was more chilling than the pounding. Lu Chenzhou pressed Zhou Zhengping into the corner and quickly scanned the mountains of clutter piled up around them. His gaze fell on several long, plastic-wrapped objects leaning against the wall. He tore off the plastic — they were several discarded, slender aluminum alloy profiles used for sealing balconies. Long enough. Strength unknown. A soft *click* came from the security door — the lock had opened. Lu Chenzhou grabbed two of the profiles, turned, and shoved one into Zhou Zhengping's hand. "Hold tight! Lay it across! To the opposite side! Hurry!" Zhou Zhengping's hands were shaking so badly he could barely grip it. Lu Chenzhou ignored him. He rushed to the security grate, thrust his profile out through the mesh gap, and pushed the other end desperately toward the edge of the opposite rooftop. Metal scraped against concrete with a piercing screech. The profile was too light, swaying in mid-air. From the entryway came the dull thud of the security door being pushed open and hitting the wall. Footsteps, more than one set, quickly flooded in. Lu Chenzhou shoved the second profile out alongside the first, pressing them tightly together to increase the width and provide a pitiful bit of stability. He turned and snarled at the terrified Zhou Zhengping, "Climb across! Now! Look ahead, don't look down!" Zhou Zhengping stared at the two slender, trembling metals reaching into the void, resting on the edge of the opposite building. He looked at Lu Chenzhou's near-ferocious expression, and then at the approaching footsteps from the direction of the balcony door behind them. Finally, driven by the instinct to survive, he let out a short, choked whimper. On hands and knees, he scrambled onto the piled-up clutter, trembling as he grabbed the security grate. Lu Chenzhou gave him a shove. Clumsily, Zhou Zhengping swung one leg out through the mesh and stepped onto the parallel profiles. The profiles sank sharply, emitting a teeth-grinding creak of bending metal. "Go!" Lu Chenzhou barked. Zhou Zhengping closed his eyes, lay his whole body flat on the profiles, and began inching forward. His weight caused the two hastily placed...