As I recall, Zhou Yang had invited Zhang Bing to check out his microblog that night. When Zhang Bing died, we couldn't find his cell phone which had obviously been taken away by the murderer!

Perhaps the murderer was inspired or triggered after reading Zhou Yang’s post and decided to kill everyone on the ghost bus that night. The first people he located were the hostesses of the nightclub. Zhang Bing must have kept their information on his cell phone so he contacted them using Zhang Bing's phone.

At the time, I assumed the murderer stole one of the hostess' cell phones out of greed but now it seemed he had another reason. There must have been chat records that he didn’t want the police to find.

Then, the next easiest thing was to locate Zhou Yang. The murderer fabricated some reason to trick Zhou Yang out and kidnapped him, forcing him to call Luo Youyou. He probably obtained Dali’s name from looking at her cell phone.

This all made the murderer less mysterious and fantastical. His murder pattern had its own rules, and now, the trail has gone cold for him! Yet, we had acquired much information!

Upon listening to my analysis, Xiaotao said, "I think we should start with Zhang Bing! The murderer could be someone who has past grievances with him."

"Since he’s already killed Zhang Bing, why keep killing?" Bingxin wondered out loud.

"Maybe he’s addicted to killing. From his sophisticated modus operandi and careful thinking, this man definitely has experience in committing murders. A man like him regards killing as a game and a challenge!"

"So, the case has nothing to do with the ghost bus?" asked Bingxin.

"Let's take a two-pronged approach!” Xiaotao declared. “We have to find out more about the ghost bus. This suspicious bus haunts Nanjiang City late at night, causing unwanted rumors and panic among the public. We can use this opportunity to take it out!"

Dali and Luo Youyou returned to the store, while the three of us headed to the station. We held a case discussion and summarized the information in our hands.

Zhang Bing had quite a lot of enemies, and his many debts had him running from loan sharks. He had to hide and stay on the move with no fixed place of residence. It was probably for this reason that he cooperated with human traffickers to partake in such a contemptible business.

Zhang Bing's laptop was filled with debt transactions. The police made a list and were ready to investigate each and every one of those transactions.

The police were also investigating several chemical plants in Nanjiang City. Officers were also assigned to investigate the original crime scene of Zhang Bing’s murder, focusing on passing vehicles at the time. However, due to the remoteness of the location, no witnesses were found.

That night, we waited for the ghost bus again but found no signs of it. The police tracked down a bunch of people who had grievances with Zhang Bing. After examining all the suspects brought back for questioning, none of them fit the characteristics of the murderer.

On the third night, the five of us headed to Redbud Road once more. By this time, we had completely lost our initial enthusiasm. After two consecutive late nights, we were exhausted. As soon as the clock struck midnight, Xiaotao sighed, "Looks like we waited for nothing again."

"It's boring to stand around here doing nothing,” grumbled Bingxin. “Let's play a word game. I’ll go first... Too big a tail.[1]"

"Amateur…” mocked Xiaotao. “Luring the tiger out of its den[2]!"

The two got into the game, finally stopping at “do whatever you please” when they failed to find a corresponding idiom.

Luo Youyou suddenly pointed into the distance and shouted, "Look over there!"

Fog enveloped the street as the outline of a bus gradually appeared. Seeing the ghost bus for the first time, Xiaotao opened her mouth in amazement, “How can this be!"

We stood next to the stop sign so the bus pulled up right in front of us. As we filed in, I grabbed a small vial to store a sample of the fog.

After getting on the bus, we immediately found our seats. Bingxin watched in surprise as I studied the contents of the vial. "Can you keep a sample of the fog?" she asked.

"Look carefully at what it is," I urged.

After further examination, Bingxin analyzed, "This gas is heavier than air." She reached out and touched the vial, "It’s cold... It’s carbon dioxide!"

"Yes,” I nodded. “It’s most likely dry ice. That’s why the fog is so dense and the temperature is lower near the fog!"

As soon as I stated my conclusion, they all seemed enlightened. The eerie atmosphere was mostly diffused by now. In fact, my main goal tonight was to expose its hocus-pocus and prove that the ghost bus was fake.

“Then what about the ghosts sitting on the bus?" Dali pointed out.

"That?” I scoffed. “In fact, I thought about it for quite some time when I went back the other day. Finally, I realized the trick to it was–"

I walked to the front window and sat down. Then, grabbing a laser pointer out of my pocket, I aimed it at the window. When the spot of light moved back and forth across the glass, the others immediately realized what the problem was. When it passed through the center of the glass, the light transmittance deteriorated.

I knocked on the window and explained, "This is a sort of optical glass. On the surface, it looks normal. In fact, its light transmittance is different from normal glass. Perhaps someone deliberately arranged this. So, when light passes through, the silhouette of a person is revealed on the ground or on the wall as if the bus is full of people."

"Is it all fake?" Luo Youyou seemed disappointed.

I nodded, "I was skeptical from the moment I got on the bus. I’m not an atheist but I’m used to verifying the authenticity of strange phenomena first instead of taking them at face value."

"Song Yang’s practice of seeking the truth is worth learning!" praised Dali.

"Since all this is fake, let's talk to the driver!" suggested Xiaotao.

She stood up, walked towards the driver's seat, and flashed her badge. "Stop the bus. We’d like to have a word with you!"

But no matter what Xiaotao said, the driver showed no response. When I walked up to him, I noticed his impassive, vacant eyes in the reflection of the windshield, like those of a dead man.

"This guy may have mental problems. We might as well stay till the last stop and see where that leads us."

Right then, a crisp snap sounded through the bus–Dali was playing with his newly bought Zippo lighter. At the flash of the flame, the driver suddenly screamed, "Fire! There’s a huge fire! Help!"

The carriage suddenly tilted, prompting me to hold on tightly to my seat while Xiaotao fell into my arms.

Then the bus swung to the other side, our bodies undulating and swaying in the same direction. Dali, Luo Youyou, and Bingxin screamed in fear. We watched the windows shake and the lights in the bus flicker.

The bus moved like a slithery snake on the road, barely stabilizing after several zigzags. At this moment, I was in my seat with Xiaotao pressed on top of my body. She covered her head with her hands as if she had bumped herself.

Gently massaging her head with my fingers, I asked, "Does it hurt?"

"I’m alright!" Then, she snapped, "Is he trying to kill us?"

Before I could say anything, she stood up and charged towards the driver, pulling out the bus key without warning. The bus came to an abrupt halt.

"Get out!" Xiaotao demanded.

However, the driver remained silent and motionless, turning the steering wheel as he looked straight ahead. It was as if the outside world had nothing to do with him...

[1] A Chinese idiom alluding to leadership rendered ineffectual by recalcitrant subordinates.

[2] Lure the enemy away from his base.