Instead of leaving the scene, I called Xiaotao and told her what happened, then I asked her to come here and bring my tools along as well.

When they heard that I’d been attacked, everyone rushed over immediately.

“Are you hurt?” Xiaotao asked the moment she arrived.

“No,” I shook my head. “Do you remember that mysterious guy who saved us that time? He was here again.”

Xiaotao glanced at the cut steel pipe and was stunned. “Your mysterious bodyguard is so good at this it’s terrifying! But why didn’t he just catch those people? He could’ve done so easily!”

I shrugged. Who knew what that guy could be thinking?

I asked Xiaotao to hold the UV lamp and checked the footprints on the ground with my Autopsy Umbrella. There were three sets of footprints—one from the mysterious guy, another from a pair of size 40 sneakers, and another from a pair of size 35 leather shoes. I asked Xiaozhou to take a plaster cast mold of the footprints as evidence.

“Do you think these two people are related to the serial murders?” asked Xiaotao.

“Most likely,” I replied. “They were probably trying to kill me…”

But that was just a guess. If they really wanted to kill me, wasn’t this method a little bit too inefficient? Why didn’t they just ambush me and stab me with a dagger?

I noticed the solidified cement on the steel pipe, yet there were no fingerprints on it. Apparently, the killer was wearing gloves. At that moment, Yuanchao returned from the other side of the alley, holding the exact same steel pipe in his hand.

“I got this at a construction site nearby,” he said.

So the killer didn’t bring it with him in the first place? Why did this seem like a rushed attack?

“Why did you buy sanitary pads, Song Yang?” asked Xiaotao.

“Oh my god!” I slapped my forehead. “Bingxin is still sitting on the toilet waiting for this!”

“You should’ve just asked me,” said Xiaotao. “I’ve got sanitary pads in my bag. Don’t go out alone at night ever again, understood?”

“Okay!” I nodded.

After investigating the scene for a while, we returned to the hotel. In addition to the identity of the killer, I was much more curious about the identity of my mysterious bodyguard. We were still walking by the road, and I suddenly turned and walked in front of an approaching car.

The car stopped with a loud screech, and the driver yelled, “You fucking idiot! Are you trying to kill yourself?”

“What the hell are you doing?” Xiaotao asked with shock.

“I wanted to see if that mysterious guy would show up and save me,” I replied.

“You’ve got to be joking!” cried Xiaotao. “Isn’t that a bit too risky? What if you actually died? If you want to find out who he is, then we should be using our investigating skills to find the answer instead!”

The next day, Xiaotao told Bingxin to rest for the day. We then went out to visit the auto repair shops in town together. There were only a few auto repair shops here, so even before noon, we made a major discovery. There was a mechanic named Cao Dazhuang who went missing last year.

“Did you report him as a missing person?” I asked his boss.

The boss showed me a text message Cao Dazhuang sent to him last year, which read, “Sorry I have to leave without saying goodbye, Boss. My cousin needs help in the city, so I have to go. You don’t need to pay for my salary this month!”

This was a usual ploy used by murderers. I believed that the victim was indeed Cao Dazhuang, but I still required DNA evidence. We asked the boss for Cao Dazhuang’s address, and he replied, “He rented a room in town, but he probably moved out a long time ago.”

We still asked for the address anyway, and tracked down the landlord of the room and asked him about Cao Dazhuang. He informed us that Cao Dazhuang left without saying anything, but his friend had come and helped him pack. The friend even paid his utility bills.

“What was that friend’s name?” I asked.

“I don’t remember,” the landlord shook his head. “It was more than half a year ago after all.”

“Tell me anything you can recall about the friend.”

The landlord thought about it for a while and answered, “I think he was a tailor. I once saw this man in his shop and even talked to him about this once.”

I asked the address of the shop he mentioned, and it really did turn out to be Zhang Qiang’s shop. Xiaotao and I exchanged looks. I was pretty sure that this case was connected to the serial murders now.

We thanked the landlord and left. Xiaotao asked me if we should go back to the tailor’s shop, but I said no.

“Oh, that’s right!” Xiaotao laughed. “It’s your usual tactic, isn’t it? Don’t alarm the suspects!”

The more the police suspected someone, the less they would make moves against that person—this was a common tactic used in criminal investigations. It seemed that, like me, Xiaotao was suspicious of Zhang Qiang!

I’d developed a habit after investigating many cases. If I suspected someone, I would imagine them committing the crimes and see if the image fit their characteristics. At present, it seemed that putting Zhang Qiang fit the position of the murderer quite well.

Xiaotao asked me what our next move would be. I told her that I needed some time to sort out my thoughts, so she suggested going out for lunch.

I bought a map of the whole county from the newsstand by the roadside, and then went to a fast-food restaurant with Xiaotao. I spread the map on the table and marked the resident locations of the four victims. As Xiaotao returned to the table with our food, she asked, “Are you going to use your divining technique again, Detective Song?”

“No,” I shook my head. “I was just thinking about the points where all the victims intersect.”

“Well, they’re all beautiful young women…”

“What you’re talking about is their similarities,” I corrected her. “I’m talking about where they might intersect. In other words, where would they all go despite having different occupations?”

“Young women like clothes, usually,” offered Xiaotao. “Perhaps they were targeted by the murderer when they ordered clothes at the tailor’s shop. The couple are getting more and more suspicious…”

“You think so?” I asked.

“Perhaps I should send officers to investigate where they had been before they died, so we can verify this.”

“Okay,” I nodded. “Let’s do a simulation of the crimes this afternoon!”

“What?” cried Xiaotao, nervous.

“Don’t worry,” I assured her. “It’s just a normal simulation, not Murder Reenactment.”

We went back to the police station and held a short meeting discussing the case. Xiaotao instructed an officer to investigate the whereabouts of the four victims a month before their deaths. Cao Dazhuang’s relationships were to be investigated too. After that, Xiaotao and I went to an empty conference room to simulate the first murder. According to the case file, the victim was disfigured with hot oil when she was still alive, while the fatal injury that killed her was the blow to the back of her head. This was where I detected an anomaly.

“Perhaps there were two murderers,” Xiaotao theorized. “Just as you suggested earlier!”

“That’s not what I’m worried about,” I replied. “If we were the murderers, what should we do to make sure the police never suspected us?”

“First of all, we would make sure not to leave any fingerprints, so we must wear gloves. Secondly, the murder weapons must not be too specific, like electric drills or rare chemicals, which are too easy to trace. Apart from that, the body should be discarded in an isolated place. The later it is discovered, the better it is for the murderers.”

“And if you’re a tailor and the victim was wearing the clothes that you made,” I continued, “would you take it off?”

“Of course I would!”

“What do you think is the most suitable method of disfiguring the victim?”

“Probably alkaline water,” replied Xiaotao. “Edible alkali can be bought anywhere. It wouldn’t be suspicious when it’s found, it can be stored anywhere, and it’s easy to clean up. Burning a pot of hot oil is a bit too troublesome, not to mention the fact that it would leave unmistakable traces.”

“Exactly!” I nodded. “Now you understand why I feel the first murder case was a bit too messy—almost like the murderers were amateurs! Yet in the subsequent cases, the murders seemed much more professional. The murderer even tried to mislead the police with local folklore, which none of the police believed, by the way. Perhaps… perhaps the first murder was a passionate crime, done in the spur of the moment, and the other murders were just copies of the first one to mislead the police!”

At that point, my mind seemed to clear and I finally saw a path towards the final answer of the case.