Chapter 209: A Final Farewell

Humans are curious creatures. The moment both of them said “Oh” in unison, I realized they were both desperate to know the answer. Honestly, I was also watching their reactions, trying to figure out if my own guess was right. Team Leader Li and Xiao Liu were afraid we’d beat them to the killer, so they never told us what they’d found in this crucial clue.

But people don’t need words to give away the truth—a look, a subtle change of expression, even a small gesture will do.

I paused, speaking slowly as I watched their faces. “You detected a second DNA sample, different from the killer in the first story. And this one belongs to a woman. But the two DNA samples are so similar they’re practically identical—the kind of match you’d find between immediate family. Twins, in fact. To put it in simple terms: fraternal twins, a boy and a girl.”

Zhang Qinrui, who’d been standing quietly behind them, spoke up at the mention of medicine. “That’s right. From a genetics standpoint, identical twins come from a single egg, so their gender and DNA are extremely close. As you said, they’re like two cookies cut from the same mold.”

Zhang Qinrui stepped forward and added, “For fraternal twins, two eggs can produce siblings with big differences. Boy-girl twins are more common that way.”

I understood that under this theory of ‘multiple killers,’ Zhang Qinrui had jumped to the conclusion there were twins involved. But he overlooked a rare, though not impossible, scenario—a true hermaphrodite, a chimera.

While Guan Zengbin was carefully piecing the bowl fragments back together, he chimed in, “But the genetic markers you mentioned show it’s from a single egg cell—a pair of boy-girl twins where the Y chromosome is missing, right?”

I didn’t really get all the technical stuff he was saying, but I caught the gist.

Zhang Qinrui nodded. “Exactly. Which means the killers are a brother and sister.”

Xiao Liu continued, “Wu Meng, this should finally put your doubts about multiple killers to rest. We have solid proof there’s more than one. Even without the two DNA samples, the fact that there’s both a male and female points right to it. And their relationship speaks volumes.”

I crossed my arms, waiting for Xiao Liu to go on.

He chuckled. “You see it too, right? The killers are twins—brother and sister, or sister and brother, doesn’t matter. What matters is their actions are eerily alike.”

He fixed his gaze on me, saying seriously, “Some people call it a kind of telepathy that only twins share. Or maybe it’s just destiny at work.”

“True,” Zhang Qinrui agreed. “Medical science still can’t fully explain why twins mirror each other so closely. But as Marx once said, material conditions shape consciousness. If their DNA is 99.9% identical, it’s not so strange their minds act the same.”

“If the killers are a pair of boy-girl twins, that would explain a lot,” Xiao Liu said, brimming with confidence. “And you mentioned hearing three voices in the sewer, right? I’d bet the little girl is their child. Since the twins are close blood relatives, their kid most likely has mental issues. That’s why this family is living down in the sewers.”

He went on. “We found the killers’ bowl, their bedding—blankets and comforters, even a plushie—in the sewer. I’m guessing when Wu Meng was chasing the killer, the little girl dropped her toy in her panic.”

I shook my head. “All right, so let’s say there’s a family of three—the killers and their child. But why go on a killing spree? These aren’t random targets—they were chosen. And those English letters at the crime scene, what do they mean? Can you answer that?”

Xiao Liu rubbed his mustache, thinking. “They kill because society can’t accept their relationship.”

“Hand me the map,” Xiao Liu said sharply.

A team member brought him the map. He studied it, then pointed and explained, “My theory is, the couple started killing because these people saw their daughter living in the sewer. The child isn’t just mentally challenged—incest makes deformity much more likely. So these people saw the girl and the parents became enraged, leading them to murder.”

“When they entered the sewer,” Xiao Liu drew a long line across the map, connecting the death sites from three different cases.

“These three places,” he tapped the map, “are where all the cases took place. Seems random now, but look at this yellow line—it represents the sewer’s path. According to the map, all three places are connected. It makes sense the little girl went above ground before. And if people saw her and treated her like a freak, her parents would be furious. That’s why they killed them.”

I stayed silent. Of course the sewer pipes all connect, otherwise where would the water go? Xiao Liu’s explanation had some holes, but was still plausible. It also explained why the killer’s family lived in the sewers—though only if there were truly several killers.

“But what about the English letters left at the scene?” I pushed the question again.

Xiao Liu shrugged before answering. “It’s obvious—these phrases really don’t translate well into Chinese. You lose their meaning if you try. Things that are hard to translate are usually slang or idioms unique to another culture.”

He paced back and forth, musing, “So these phrases we’ve managed to translate are probably homegrown, their own kind of code. Maybe curses or something like that.”

Xiao Liu’s imagination was running wild. “Carving those words, maybe it’s meant to avenge their daughter—maybe those marked can never find peace, something like that. They want to prove their girl isn’t a monster.”

Listening to Xiao Liu, I couldn’t help but worry. His multi-killer theory was detailed and logical, every step fitting neatly. Yet, I still believed there was only one killer.

At this point, Xiao Liu rolled up the map and said to everyone, “Wu Meng, I might just beat you to catching the killer. Back when I was on Team Leader Shao’s team, I always heard about how amazing you were. But I’ve left his team now, and maybe I’m not too shabby myself, right?”

“But what if you were wrong from the very start?” I shot back.

Xiao Liu waved dismissively. “We’ve got evidence you don’t know about—key clues that will lead us straight to the killer. Wu Meng, you shouldn’t always assume you’re right and everyone else is wrong. I know your talent is off the charts, but I’ve always worked harder and paid more attention to detail. This time, I’ll make sure you see it for yourself.”

Gu Chen, never one to keep quiet, jabbed a finger at Xiao Liu. “If you’re going to brag, make sure you bring the killer in front of us first. Anything can happen until then. Who says we won’t beat you to it? Ever heard of a dark horse?”

“You’re out of luck,” Xiao Liu replied, glancing at Team Leader Li. “Let’s get moving.”

Team Leader Li nodded.

I had no idea what crucial evidence Xiao Liu had found. No one was about to tell us, so we’d just have to investigate on our own.

We’d just walked a good distance when Xiao Liu suddenly doubled back, heading for us alone.

We eyed him with suspicion and he looked at us just as carefully. After a pause, he finally spoke. “This time, the team that catches the killer last will be eliminated. If you fail, no matter how much Old Bai favors Team Leader Shao, he won’t have the nerve to bring you back again.”

Xiao Liu’s eyes were red as he went on. “Solving cases with you all was one of the happiest times I’ve had. But after today, it’s all out of our hands. Nothing lasts forever, especially when the road ahead gets hard. Better to be the head of a chicken than the tail of a phoenix—I hope you’ll understand that one day.”

“I’m just an ordinary guy.” Xiao Liu didn’t look back. “Maybe I’m not as talented as you, but I’ve worked way harder. Heaven has to take notice.”

“Pretender,” Gu Chen muttered.

But Xiao Liu was already gone. His last words were his farewell to us.