The night grew deep.

In the old apartment building, everything was silent, with only a few sparse cricket chirps outside the window, accentuating the deathly stillness within. Chen Mo's home, like the man himself, was simple to the point of desolation. Cement floor, white lime walls, a few basic pieces of furniture, without any unnecessary decorations. A faint smell of dust lingered in the air, mixed with the distinctive dampness of an old house.


The only light came from a dim desk lamp. Under its yellowish glow, the old feature phone resembled an archaeological artifact, lying quietly on the desk. Chen Mo sat at the desk, his silhouette casting a huge, frozen shadow on the wall. He had maintained this posture for a long time.

This was his third attempt to charge the phone. Using a mismatched universal charging cable, he carefully aligned the two metal contacts with the tiny ports on the phone's battery. The screen finally lit up, displaying a red, nearly empty battery bar with a constantly flashing lightning symbol beside it. It was still alive, but could die completely at any moment.

Chen Mo breathed a sigh of relief, feeling his heartbeat stabilize along with that faint electrical current. He dared not delay for even a moment and immediately turned on the phone. The harsh yet nostalgic startup music played, sounding particularly abrupt in the silent night. After entering the main interface, he quickly found the application named "My Diary."


The icon was a notebook with a lock. He tapped on it, and a password input box popped up on the screen.

"Please enter password." The cold electronic characters appeared in the center of the screen.


Chen... Mo frowned. He first tried entering Song Wenjie's birthday, the screen displayed "Password Error". He then tried the pinyin initials of Song Wenjie's name, the phone's keys made a dull "click" sound, but the result was still "Password Error". He tried every possible number and letter combination related to Song Wenjie that he could think of, including his student ID, the last few digits of his ID card, and even his old house number.

Each hopeful attempt was met with those four cold red characters.

The phone's battery was visibly draining, that red text seemed to mock his futile efforts. A sense of frustration washed over him like a tide, Chen Mo irritably leaned back in his chair and pulled out a cigarette from his pocket and lit it. Through the swirling smoke, he stared intensely at the phone screen, as if trying to burn through it with his gaze. Ten years, and the truth was locked in this small metal box, separated by a password he couldn't crack. This feeling was more torturous than having no leads at all.

He took a deep drag of his cigarette and leaned down once more, preparing to try the last set of numbers he could think of. Just as his fingers were about to press down, the screen flickered once and instantly went black.

The battery had died.

Complete darkness swallowed the last bit of light. Chen Mo's hand froze in mid-air, ash from the cigarette in his mouth broke off and fell onto the cold shell of the phone. He felt as if a stone was lodged in his chest, heavy and suffocating. He sat still for a long time, until the cigarette in his hand burned down to the end, scorching his fingers, which finally snapped him back to reality. He didn't try to charge the phone, but simply put it away along with the photo album, placing them in the innermost pocket of his shoulder bag, then got up and walked toward the bedroom.

That night, he slept restlessly. His dreams were filled with that stormy night, Song Wenjie's pale face, and his own powerless explanations when facing his superiors back then.

The next day, the bureau's office building was as busy as usual. Phone rings, keyboard clicks, and hurried footsteps in the hallway intertwined together, creating a symphony of police daily routine. When Chen Mo arrived at the office, most of his colleagues were already there. As usual, he walked to his seat without saying a word, turned on his computer, and began browsing internal reports.

His desk was in the most inconspicuous corner of the office, piled with dusty files and various items, like a forgotten island.

"Brother Chen, good morning." A clear voice sounded beside him.

Chen Mo looked up and saw Li Xiaodong standing by his desk with a steaming cup of tea, smiling. He was wearing a crisp uniform and looked energetic, forming a stark contrast with the somewhat tired senior colleagues around him.

"Morning." Chen Mo responded with a nasal grunt, his gaze returning to the computer screen. For this kind of overly enthusiastic greeting, he instinctively kept his distance.

Li Xiaodong seemed unbothered by his coldness. He naturally pulled over an empty chair from nearby and sat down, placing his teacup at the corner of the desk. He leaned forward slightly, assuming a posture of humble inquiry.

"Brother Chen, I just arrived and there's still a lot I don't understand. Yesterday I heard from the squadron leader that you used to be the most formidable investigator in our bureau, with especially rich experience in handling cases." Li Xiaodong's tone was sincere, his eyes full of admiration. "Especially those old-school investigation techniques that can't even be learned from textbooks anymore. When you have time, could you teach me? Like how to discover clues from a pile of seemingly useless old materials."

Chen Mo's eyelid twitched. He glanced at Li Xiaodong, this young man whose every sentence was perfectly delivered, expressing respect while clearly stating his purpose. The leader's "concerned" words from yesterday immediately echoed in his mind. He laughed coldly inside, though his face remained expressionless.

"There's no special technique, just the hard way—read more, think more," he answered concisely, his fingers unconsciously sliding over the mouse.

"Are you investigating any cases right now?" Li Xiaodong asked casually, while his gaze inconspicuously swept across Chen Mo's desk.

"Just browsing," Chen Mo replied perfunctorily.

At that moment, Li Xiaodong's gaze became fixed. He noticed several A4 pages freshly printed from the printer next to Chen Mo's monitor, with a bold-faced title that was quite eye-catching—"Management Regulations on Filing, Archiving and Destruction Procedures for Criminal Case Files Over Ten Years Old (2012 Revised Edition)".

Li Xiaodong's pupils contracted almost imperceptibly. A cold case from ten years ago? This timing was too sensitive. He immediately thought of some records about Chen Mo in the archives, the case that had marked a turning point in his career, which seemed to have happened ten years ago. He didn't ask any further questions, just nodded, the smile on his face remaining gentle.

"I see. I won't disturb you any further then, Brother Chen. If I have any questions in the future, I'll come to you for guidance." Li Xiaodong stood up, picked up his teacup, and politely turned to leave.

Watching Li Xiaodong's back as he returned to his seat, Chen Mo's gaze grew profound. This young man was even more perceptive than he had imagined. It seemed that from now on, he would have to be even more careful with every step he took.

He closed the browsing page on his computer, picked up the printed regulations and read through them once more, then got up and walked toward the archives room.

The archives room of the city bureau was in the basement of the office building, cold, quiet, with the air always filled with the mingled smell of paper and dust. The administrator was an old police officer in his fifties, wearing reading glasses, who was buried in sorting through a pile of yellowed case files.

"Mr. Wilson." Chen Mo knocked on the door.

The administrator looked up, somewhat surprised to see Chen Mo. "Oh, it's Old Chen, what a rare visitor. What wind blew you here today?"

"I'm here to check something." Chen Mo got straight to the point, "I want to access the files of a case from ten years ago."

"From ten years ago?" Mr. Wilson adjusted his glasses, "Which one? Do you remember the case number?"

"The Song Wenjie accidental falling death case." Chen Mo said slowly and deliberately.

Upon hearing this name, the smile on Mr. Wilson's face froze momentarily. He lowered his head, pretending to flip through the registry, and after a good while, he finally spoke slowly: "Song Wenjie... I have some impression of this case. Wait a moment, let me check the computer."

He typed away on the computer for a long time, the screen emitting a soft blue light that cast his face in a somewhat dim and unclear light. Finally, he shook his head and looked at Chen Mo with a troubled expression.

"Old Chen, it's really unfortunate. The files for this case... I'm afraid they can't be accessed anymore."

"What do you mean?" Chen Mo's heart sank.

"You know, in our basement, there was a water leak during the rainy season a few years ago, which happened to flood a batch of old case files. Although we tried to salvage them at the time, some were too severely damaged by moisture, the writing became blurred, and the paper turned brittle, making it impossible to read through them." Mr. Wilson sighed, pointing to several large boxes labeled "Damaged" in the corner. "The files for that case are among them, and we've already followed the procedures for reporting damaged documents. What rotten luck, of all things, it had to be this one that got damaged."

Chen Mo stared fixedly at those few boxes, his fists unconsciously clenched at his sides. It was too coincidental. How could it be so coincidental? Why not leaked earlier or later, but precisely that batch of files was flooded? This kind of excuse couldn't fool even a three-year-old child.

He knew there was no point in asking further questions; Mr. Wilson was just a doorkeeper, and surely someone he couldn't afford to offend had given instructions behind the scenes. He didn't say anything more, just nodded and turned to leave the archives room.

Back on the ground level, the glaring sunlight made him feel dizzy. The small hope that had been kindled yesterday was instantly extinguished by a bucket of cold water. The phone wouldn't turn on, the files were "damaged"—both paths were blocked.

Chen Mo didn't return to his office but instead walked to a secluded corner, took out his phone, found a number that had been buried for many years, and dialed it. The phone rang for a long time before it was answered.

"Hello? Who is this?" came a voice from the other end, tinged with wariness and unfamiliarity.

"Old Zhang, it's me, Chen Mo."

There was a few seconds of silence on the other end of the phone, then the voice became somewhat unnatural. "Chen Mo? Oh... it's you, Old Chen. What made you call me? I was transferred to the traffic police department long ago."

This Old Zhang was his colleague who used to go to crime scenes with him back then.

"I want to ask you, how much do you remember about Song Wenjie's case?" Chen Mo asked directly.

"Song Wenjie?" Old Zhang's voice suddenly became vague, "Oh, that happened so many years ago, how could I remember clearly? Wasn't the case closed back then? An accident, it was just an accident."

"Are you sure it was just an accident?" Chen Mo pressed.

"Then... what else could it be?" Old Zhang stammered, his suppressed breathing coming through the receiver. "Old Chen, let me tell you, why... why are you bringing this up again? It's all in the past, people should look forward. Some things, the less you know, the better. Take my advice, don't investigate anymore, those waters... they're deep, you can't stir them up."

After speaking, as if afraid Chen Mo would ask anything else, he hurriedly said, "I have something to attend to, I'll hang up first," and ended the call.

Listening to the busy tone coming from his phone, Chen Mo stood there, motionless for a long time. Even his fellow officers who were at the scene back then were this scared, showing just how powerful the forces behind this were. The case files destroyed, witnesses tight-lipped, all leads seemed to have been cut off.

He felt a sense of helplessness like never before.

In the evening, Chen Mo didn't go to the noodle shop, but went straight home. He threw himself onto the sofa, smoking one cigarette after another, until the room was quickly filled with smoke. Frustration and anger collided in his chest, but could find no outlet.

He didn't know how long he sat there, until the cigarette pack was empty, then he got up and took out that photo album from his shoulder bag. He needed something to calm his emotions.

He flipped through it page by page. In the photos, Song Wenjie smiled so brightly, full of hope for the future. When he reached the middle, a photo made him stop.

The photo shows Song Wenjie and his sister Song Wenqi together. The siblings are snuggled close to each other, smiling happily at the camera, with a Ferris wheel in some park as the background. That was their most precious memory. Chen Mo's gaze lingered on the photo for a long time, then he unconsciously pulled the photo out from under the plastic sheet of the album.

Just as he was about to put the photo back, he felt that the back of the photo seemed somewhat uneven. He turned the photo over, and in the dim light, he saw a string of numbers written in ballpoint pen on the back. The handwriting was very light, almost impossible to notice without careful examination.

The string of numbers was: 19920815.

This string of numbers looked meaningless, like a code jotted down randomly. Chen Mo stared at it, repeating it over and over. 1992...0815...

Suddenly, a thought struck his confused mind like lightning!

Song Wenqi! He remembered Song Wenqi's information, her birthday seemed to be August 15th, and 1992 was the year she was born.

This string of numbers was Song Wenqi's birthday.

Chen Mo's heart suddenly began to race. He practically jumped up from the sofa, rushed to the desk, and fumbled to find the charger to plug in his phone. He stared intently at the screen, time becoming incredibly slow in this moment. After a few minutes, the phone finally accumulated enough power to turn on.

With trembling hands, he entered that string of numbers: 19920815.

Then, he pressed the confirm button.

This time, the red warning "Password Incorrect" did not appear on the screen. Instead, the locked notebook icon made a "click" sound, as if opening a real lock.

The screen changed, and the first page of the diary clearly appeared before his eyes.