Rising in the cold gleaming metal elevator.

After a brief silence, the middle-aged woman finally spoke, "I think I know why Ruka barked at you."

"Why?" I became increasingly curious.

"That apartment on the 18th floor. It's strange. Strange noises keep coming from there late at night." The middle-aged woman lifted her dark and thin face. She looked unhealthy as if suffering from chronic insomnia.

"I live downstairs, and I'm a light sleeper. Any slight noise disturbs my sleep. It's been happening from time to time on the floor above, and I couldn't take it anymore, so I complained to the property management."

"The result was, the property management told me that the apartment has been unoccupied all along!"

After saying this, the middle-aged woman shivered, tightening her knitted shawl.

She seemed to be sensitive to the cold, dressing so warmly even in hot weather.

I asked, "What did you hear? As far as I know, some houses can make strange noises due to thermal expansion and contraction."

"I know the principle you're talking about, but the sound I heard doesn't come from thermal expansion and contraction. It's like someone sharpening a knife."

"Sharpening a knife?"

My eyebrows twitched, involuntarily recalling the sound of chopping meat at the Baozi shop. Hearing such a sound in the middle of the night was indeed terrifying.

"I called the property management people to come and listen at night, but what's scary is that they couldn't hear anything. It's like I'm the only one who can hear that sound, and they said I'm hallucinating."

The middle-aged woman reached out to stroke the head of the black back and smiled bitterly.

"Perhaps you don't believe it, do you? Ruka used to be very obedient, never barking recklessly. It's only after moving to this neighborhood that these problems started."

"I shouldn't have told you all this, considering you're going to live here. I'm sorry, I spoke too much."

"No, ma'am, you're kind, and I appreciate it." I smiled at the middle-aged woman. "You kept saying not to stay outside at night. Why is that?"

"Do you believe what I said?" The middle-aged woman's tired eyes showed surprise.

Ding.

At this moment, we reached the 17th floor.

The elevator door hadn't fully opened, but Ruka desperately tried to get out, as if trying to escape for its life. The middle-aged woman had to pull it back from being dragged out and looked at me at the door as if wanting to say something.

"Ma'am, this is my business card. If you have anything else to say, feel free to contact me anytime." I took out my business card and handed it to her.

The middle-aged woman took the card, glanced at it with a mix of belief and doubt, and accepted it out of courtesy.

The elevator door slowly closed, and I picked up my phone, preparing to check if there was anything around me.

The phone's default was the rear camera. The elevator door hadn't completely closed yet, and I happened to capture the back of the middle-aged woman leaving with the dog.

Seeing the screen, my heart skipped a beat.

There seemed to be a black shadow on the back of the middle-aged woman, fleeting and unclear. I wasn't sure if I was mistaken.

The elevator door was fully closed, heading up, and I couldn't go out to confirm.

Forget it. If she encounters something strange, maybe she'll contact me.

No longer dwelling on it, I switched the camera to the front.

My slightly pale face appeared on the screen. I moved the camera left and right, checking behind me and the entire elevator, finding nothing suspicious.

Slightly relieved, I was even more puzzled. If that's the case, why did the black back bark at me?

It obeys its owner's commands, indicating that it's not a mad dog.

Ding.

The elevator door opened again, and we reached the 18th floor.

I set aside my doubts and walked out.

In the silent corridor, there was only me. Staring at the pitch-black door, recalling what the middle-aged woman had said, I felt uneasy.

If what she said is true, this apartment is likely dangerous.

But since I'm already here, I must go in and take a look to set my mind at ease.

Taking a deep breath, I took out the key and inserted it into the lock.

Unlocking it, I pushed open the door. I stood at the entrance, cautiously lifting the black phone to scan inside the door, checking the house's interior. The house was renovated, fully furnished, and exceptionally quiet.

After watching for a while and finding no danger, I cautiously stepped into the room.

I didn't dare to turn on the light; I used the black phone for illumination.

The cold light could only brighten a small area around me. The entire house was shrouded in darkness, making it even more unsettling.

Standing at the entrance, I opened the shoe cabinet.

Rows of large cabinets were filled with various women's shoes, all in the same size. An unoccupied house couldn't have these things; someone must be living here.

And it seemed to be a single woman.

Was the middle-aged woman lying to me? We were strangers; she had no reason to do so!

Unable to understand the reason behind this, I didn't dwell on it too much. Clarifying whether this was Red Sister's house was my main goal.

Carefully walking into the living room, the cold white light gradually swept across the room. The decoration was high-end, low-key, and luxurious.

From the style and decoration, it was obvious that a woman liked it, confirming my speculation.

Thick blackout curtains blocked the windows tightly, but the house was clean and tidy, not like it hadn't been inhabited for a long time.

Suddenly, I thought of something. In case the owner of this house suddenly returns, I will be mistaken for a thief. I must resolve it quickly and find something that can prove the owner's identity.

The key is photographs! After a rough search of all the rooms, I found something strange.

There wasn't a single photograph in the house, but there were several places on the walls where traces of picture frames had been hung. These things seemed to have been deliberately collected.

The small nail holes on the wall were scattered, incongruent with the highly styled interior environment.

The class of the neighborhood, the luxurious decoration inside the house, and those high-end cosmetics brands I had only seen on TV, all indicated that the female owner of this house was a wealthy woman.

Such a woman must pay great attention to her lifestyle. Even if she wanted to replace the decorations on the wall, why would she leave the old picture frames untouched? Was she deliberately hiding something?

Is she hiding something? There's no way to verify if this house belongs to Red Sister using photographs. I thought for a moment and then considered that there should be property documents or similar items in the house that can prove the owner's identity. I resumed my search inside the house and eventually, groundbreaking findings emerge.

a large bookshelf against the wall, filled with various books, including a collection of specialized series, indicating that the wealthy woman was cultured rather than someone who had suddenly acquired wealth.

However, the main focus wasn't on that. It was on the desk drawer, the only locked cabinet in the house. It seemed to contain something very important.

I found a few paper clips in a penholder, straightened them, wound them together, forming a makeshift hook, and inserted it into the keyhole, attempting to pick the lock.

Click.

The lock springs moved, and I managed to open the lock.

Eagerly, I pulled open the drawer.

I inhaled sharply; the contents inside shocked me greatly!