Qin Guan knew this was a psychological battle.
He was well familiar with these police tactics, all kinds of tactics—in the past, he had painstakingly taught his clients how to deal with them.
He had always handled them effortlessly. At least, after fully calming himself down, he hadn't made a single mistake during Old He's repeated interrogations.
But at this moment, he was genuinely rattled.
He Zhi Sheng's aggressive demeanor opposite him was hard to withstand. Of course, this was mainly because he still couldn't grasp the other man's true intentions.
What was the point of dredging up these old cases?
Qin Guan had no idea.
The fear of the unknown and the immense confusion made his whole body tense. Old He's hard, unwavering gaze was like a sharp blade, slicing relentlessly and with deadly precision, shredding Qin Guan's reason and calm to pieces.
His heart was lodged in his throat.
He stared fixedly at Old He, abandoning his previous calm, detached "spectator" attitude, and urged impatiently, "What did the liquor bottle test show? Tell me!"
"Tell you what? You already know! There was something in that liquor!" Old He flipped another page in the file, raised his eyes, and his gaze pierced straight into Qin Guan's uneasy heart—a breach had finally been torn in this man's formidable psychological defenses. "That thing, you stole it from school! Your classmate can testify!"
There had been a classmate who saw him.
A girl. Qin Guan remembered her surname was Liu—short, dark-skinned, with one eye larger than the other, radiating an overall rustic ugliness. Of course, Qin Guan didn't dislike her because she was ugly, nor because her grades were sometimes on par with or even surpassed his. He disliked her because she was always competing with him, always copying him.
He started self-studying chemistry early; she also borrowed chemistry books to study ahead.
He sought out teachers for extra questions after school; she always did the same.
Utterly annoying.
That afternoon—Qin Guan would never forget it—the evening before the week his drunkard father died, to be precise, that Friday—the girl was still there. Of course, Qin Guan hadn't noticed her at first.
Every afternoon after school, he would slip into the school's laboratory. Though it was a county town middle school, because it was a poor county with scarce resources, the school only had one chemistry lab, which also doubled as the office and living quarters for the chemistry and math teachers.
Both teachers were very fond of the studious Qin Guan, especially the chemistry teacher. Even though he hadn't officially started teaching Qin Guan's chemistry class yet, he was more than willing to answer Qin Guan's questions and even allowed him to observe his experiments.
"This is potassium permanganate. This one looks empty, doesn't it? Actually, there's something inside—hydrogen. This is nitrogen. This is a metal, zinc. This is titanium,"
This short, thin old man loved to talk and would tirelessly explain to Qin Guan, "This yellow liquid inside? Looks like oil, right? It's not oil. It's trinitroglycerin!"
"What's its use? How to explain... you'll learn about its chemical uses as you study more. Dangerous? No, this thing isn't inherently dangerous. It has significant use in clinical medicine; it can relieve pressure on the heart, treat angina. But... it also has contraindications. It interacts with alcohol."
He explained vividly to Qin Guan, "For example, teacher here likes to drink. If I took medicine containing trinitroglycerin and then immediately drank alcohol, well, the trinitroglycerin wouldn't relieve the pressure on my heart. Instead, catalyzed by the alcohol, it would increase the burden on the heart. In severe cases, it could even cause acute myocardial infarction. That would be dangerous,"
"So you see, learning chemistry well is very important," he patted Qin Guan's shoulder encouragingly. "Study hard. In the future, whether you study medicine or pursue a career in chemistry, it will be useful. It can play a huge role."
"What classmate? Impossible. I didn't do anything. I don't even understand what you're talking about."
Qin Guan's face was cold. It took him a long moment to squeeze out these words.
Old He couldn't possibly have found out. So many years had passed since then. The chemistry teacher back then was long dead. Even if he were alive, he would never remember what he had said, let alone connect it to the accident that happened at Qin Guan's house that winter.
"Your classmate. Surname Liu," Old He said, enunciating each word clearly.
Qin Guan's heart quivered.
Sure enough. It was that detestable girl.
That afternoon—a week before his drunkard father's accident, on a Friday—both teachers had gone home. He still lingered in the lab under the pretext of reviewing his lessons until 6:30 pm. Then, "obediently," he cleaned the lab, turned off the lights, and after confirming no one was around, he opened the bottle of "trinitroglycerin" he had long since targeted. Calmly, he poured half of it into a small glass vial he had prepared.
Just as he stepped out of the corridor in front of the lab, he saw her—the girl surnamed Liu. She was carrying her backpack, books clutched to her chest, emerging from the teachers' dormitory building on the other side. Spotting Qin Guan, her mismatched eyes swept over him with a cold, disdainful glance, then flicked towards the darkened laboratory. Without a word, she lifted her chin and walked away proudly.
Just that once.
Because he ran into her, Qin Guan had to postpone his plan by a full week.
He observed her for a week.
During that week, Liu showed no signs of anything unusual. The chemistry teacher opened the small cabinet in the lab every day and noticed nothing amiss. Everything remained perfectly normal. Only then did Qin Guan feel reassured enough to carry out his plan.
The plan went smoothly. Couldn't have gone smoother.
His drunkard father accepted the food and water he brought without the slightest hesitation. He ate and drank as usual. After downing the water in one gulp, he even praised Qin Guan—a rare occurrence—though, of course, he still managed to praise himself in the process. "My son is filial after all! Filial and capable. A son takes after his father, no mistake there! The older you get, the more you resemble your old man! I didn't raise you for nothing!"
Having said this, satisfied, he picked up the bottle of liquor his "filial" son handed him, took a large swig, then turned and vanished into the snowy night, humming a tune.
After the incident, no one suspected Qin Guan—not the police, not the teachers, and not even that Liu girl. The ugly girl even secretly slipped him a note of comfort, thinly veiling her feelings: Qin Guan, don't be sad. There are still many people in this world who love you. I am willing to be your best friend and accompany you through your loneliness.
So, all these years later, He Zhi Sheng had actually tracked down that ugly freak? And that ugly freak had told He Zhi Sheng about this detail from back then?
Qin Guan's heart pounded wildly in his chest—No, impossible. If she had known back then that he stole something from the lab, she wouldn't have tried to get close to him after his drunkard father's accident. She should have been afraid and kept her distance.
Impossible.
He Zhi Sheng is bluffing.
But—Qin Guan's mind grew even more chaotic—it still came back to that question: Why is He Zhi Sheng doing this? What does he actually want?