I dashed to the auditorium, well aware that with Deng Chao's scheming, he wouldn't have prepared all the internal organs. One was bound to be missing.

On my way there, Xiaotao said, "Song Yang, we have an extra helper here. Guess who’s tracking Deng Chao’s position."

"Who is it?" I wondered out loud.

Lao Yao’s voice interrupted our conversation, "Hello, Xiao Song-Song!"

"Oh my gosh, didn't you attend the graduation ceremony?" I asked.

"I didn't manage to graduate this year so I stayed in the dorm to play games and I was evacuated with the others. Looks like not graduating was the right thing!"

No wonder I didn’t see him around.

Lao Yao explained that the school’s PA system was operated by a computer. He hacked into the school system and found a signal in the remote control PA system. The source of that signal was within campus. In other words, Deng Chao could be broadcasting remotely from any corner of the school.

"Would you like me to cut off the signal?" he asked.

"Not for now,” I replied. “We don't know what else he’s got planned. Let's go along with his little game first!"

"Xiaotao-jiejie has allowed me to temporarily take over the Skynet surveillance system. It's so freaking advanced! I feel like I'm standing on top of the campus looking down right now."

"Is there anything unusual?" I continued.

"There is a black spot that’s moving pretty quickly. Wait... isn't that you? Where are you going?"

"Don't track me. Find out where Deng Chao is!" I instructed.

Right then, Dali shouted "hello" a few times on the phone.

"What organs have you found?" I asked.

Dali's voice sounded muffled as if he were covering his mouth. "Oh my God, it’s so disgusting!” he yelled. “We found some bags nearby, all filled with bloody intestines or some other organs. It’s really gross!"

I was already at the auditorium, so I said, "Well go on then! What organs have you found?!"

"Well, let me see... Stomach... Intestines... Heart... Um, this looks like the kidney... Oh, this I know. It’s the lungs..."

Dali named quite a few human organs, but there was no sign of the liver. It was just as I expected–Deng Chao planned to cheat again.

"Put the mannequin and the internal organs under the camera and I'll be right back!"

With that, I hung up the call. At my feet was the body of the professor. Without any sharp weapons, I only had my hands. Fortunately, his chest had been ripped apart by the explosion so all I had to do was tear at the flesh to reveal the bloody internal organs. I tore the blood vessels and bile duct around the liver, then carefully removed the fatty liver and wrapped it with the clothes on the ground.

By the time I reached the lake, there was only one minute left. Dali stood there shouting, "Song Yang, hurry up!"

I sprinted to the mannequin, and almost without thinking, I stuffed the internal organs one by one into the right positions, finishing the task with five seconds left on the clock.

Time was up!

A burst of applause sounded from the speakers. "Wonderful!” exclaimed Deng Chao. “I have to admire your courage and determination. You’ve saved the lives of many policemen."

His words hit me like a bat to the head. He was targeting the police!

Deng Chao continued, "For the next test, please head to the place that neither you nor I can forget. I’ll be waiting for you!"

I glanced at the old lecture building behind me. This was definitely the place he was referring to. Xiaotao’s voice interrupted my thoughts, "Song Yang, that was a close call! We found a remote control bomb in our temporary command center. Our forces are working at full speed to dismantle the bomb."

"Evacuate now!" I urged.

Deng Chao must have guessed that the building opposite our campus would be temporarily commandeered by the police. I stood there, rooted to the spot, mind sluggish from the shock that Xiaotao and Lao Yao had almost lost their lives. Heart tied up in knots, I vowed to topple his schemes starting from this moment.

However, the fact that Deng Chao hadn’t taken other hostages meant he had other arrangements throughout the campus. His hostages weren’t just Bai Lei and the children, but all of us.

We soon arrived at the old lecture building. When we got to the third floor, I noticed a table in the corridor. There was a huge box with a hole big enough to fit a pair of hands.

In front of the box was a letter that read: "Song Yang, congratulations on finding the fourth test. There’s a deck of playing cards in the box in front of you. There are ten face up cards. You must divide the deck into two stacks without looking at them. Make sure the number of cards that are face up in both stacks are equal. Peeking inside the box will be considered as cheating. You have five minutes."

Upon reading this, I heaved with relief. This was actually a math problem, and since I was a science student, thinking logically and mathematically wasn’t an issue for me.

Dali frowned and pondered for some time, "If you’re not looking at it, how are you supposed to divide it equally?"

"He didn’t specify that the number of cards in both stacks have to be equal. Suppose I take some of them now — there are N face down cards and the other stack is 10 minus N. How can I make these two numbers equal? It’s very simple. Take ten cards and turn them over, so the number of face up cards on both sides are equal."

"10 minus 10 plus N…” mumbled Dali. “Oh, my God, how did you come up with that?!"

I was about to place my hand into the box when Dali interjected, "Wait a minute, Deng Chao wouldn't have put a poisonous snake inside, would he?"

Dali's words reminded me of the young man’s cunning nature. Adopting prudence was a good approach.

Sticking my ear to the box, I gently tapped it and waited to hear any odd sounds. But all I heard was empty silence. It seemed there weren't any living creatures waiting to ambush me. Only then did I confidently place my hand inside. However, upon answering the test, it suddenly struck me that Deng Chao never stated how I was supposed to hand in my answer this time.

Without a doubt, such a simple problem had no way of stumping me. Deng Chao must have expected this as well.

I kept my eyes on the countdown, but even at zero, there were no instructions or reply from the man. Yanking the box open, I found only playing cards and words written on the inside of the box–

"Detective Song Yang, when you see this, you should have noticed that the fourth test isn’t over yet. After all, this is the place we share significant memories. How could I let you go with a little children’s problem? This little test was just a warm-up. Go to the fourth floor. The real test is waiting for you there. Here’s a friendly reminder–you don't have much time!”

Deng Chao played me like a fiddle! Fighting back the urge to swear, I sprinted to the fourth floor.

Along the corridor of the fourth floor, I noticed that the windows were painted with numbers from "0" to "9". A student was sitting in an empty classroom with his head tilted to one side, facing the window. The curtains were drawn so the room was enveloped in darkness.

At the student's feet was a pool of old, coagulated blood, suggesting that he was killed a while ago. I walked to the front door, only to see a digital watch attached to it. The countdown showed four minutes and thirty seconds, and beside it was a piece of paper...