Chapter 4 — The City Behind the Mist

Mr. Kieu Xuan Thinh's small house is hidden behind an old pine forest, near the lake area north of the town, where the mist seems thicker than anywhere else in Van Son. Khanh Linh and Viet Hoang stood in front of the wooden gate that had faded over the years, both feeling as nervous as the meeting with Mrs. Ut Suong the day before.

After a few knocks on the door, an older man, with a thin figure but still sharp eyes, opened the door and looked out with a wary expression. "Who are you looking for?" he asked, his voice somewhat reserved.

"Hello, Uncle Thinh," Khanh Linh said, trying to keep her voice calm even though her heart was pounding. "I am Khanh Linh, daughter of Uncle Bach Vinh Son."

Mr. Thinh's eyes flashed with a clear shock, his hands clasped the door tightly as if to maintain balance. "Son's... daughter," he repeated, his voice trembling. There was a long silence before he opened the door wider, his eyes now filled with a mixture of nostalgia and worry. "Go inside, don't stand out here, it's very cold."

Inside the small, simple but neat house, Mr. Thinh invited them to sit and personally brewed a pot of hot tea with his hands that were still shaking with emotion. "I didn't expect to see Son's daughter again one day," he said, sitting down across from them. "You look so much like your father, especially your eyes."

"I came back to Van Son to be in charge of the project to beautify the old town," Khanh Linh explained, then decided to go straight to the problem that she had been mentally preparing for all night. "But actually, I came to see you today for another, much more important reason. I need to find out the truth about what really happened in the landslide fifteen years ago."

Mr. Thinh's face suddenly turned pale, his hands placed the teacup on the table with a soft rattling sound. "I don't know what you're talking about," he said, his voice somewhat evasive, different from the initial warmth.

"Uncle Thinh," Viet Hoang spoke up, his voice gentle but firm. "We talked to Ms. Ut Suong. She told me she heard an argument between Mr. Ho Xuan Truong and a worker, about the drawings not matching the actual construction, right before the night of the disaster."

Mr. Thinh closed his eyes, a heavy sigh escaped from his chest. "I've been dreading this day coming, and have been waiting for it for fifteen years," he said, his voice now weary. "I'm old, I don't have much time left to continue carrying this secret to my grave."

Khanh Linh held her breath, waiting for what he was about to say, clearly feeling that this was the decisive moment of the whole journey to find the truth.

"My father is a talented architect, careful down to the smallest detail," Mr. Thinh began, his eyes distant as if he were going back in time. "The drainage system drawing he designed for the ancient market area was calculated very carefully, based on detailed geological surveys, with appropriate pipe diameters and slopes to ensure safe drainage even during the heaviest rainy season."

"So why did that system fail?" Khanh Linh asked, her voice trembling.

"Because it was not constructed according to the original drawings," Mr. Thinh replied, his voice becoming heavy. "I saw the actual construction drawings after the disaster, during the internal investigation meeting before the official conclusion. The diameter of the drainage pipe was much smaller than the original design, and the slope was also changed, not enough to handle the large flow of water on that stormy night."

"Who changed the drawing?" Viet Hoang asked directly, even though both of them already had a hunch about the answer.

Mr. Thinh was silent for a long time, as if in an intense internal struggle before answering. "Ho Xuan Truong, the engineer supervising the project at that time, arbitrarily made adjustments to cut material costs, using cheaper pipes with smaller diameters than the design," he said, his voice shaking because he had to tell the truth that had been buried for so long. "My father, when he discovered this deviation during an unannounced inspection of the construction site, was extremely angry and demanded that it be corrected immediately before continuing with other construction items."

"So why is it that your father is the one blamed in the end?" Khanh Linh asked, her voice choked.

"Because the next night, before we could fix it, unusually heavy rain fell, causing landslides," Mr. Thinh replied, his eyes filled with tears. "And in the official investigation file that followed, the original drawings that your father had originally signed off on — before the errors were discovered — were used as incriminating evidence, as if the drawings themselves, and not the faulty construction, were the direct cause of the disaster."

Khanh Linh felt like she couldn't breathe before the truth had just been revealed. "What do you mean, someone deliberately swapped the files, causing the drawing that my father asked to be revised to disappear, leaving only the original unedited drawing, to put the entire responsibility on his shoulders?" she asked, her voice shaking with indignation.

"That's exactly what I believe happened," Mr. Thinh confirmed, nodding heavily. "But I have no concrete evidence to prove it, other than an old man's memory and a copy of the drawing that your father requested to be revised, which I have secretly kept for the past fifteen years, in case I need it one day."

He stood up, walked to an old wooden cabinet in the corner of the room, and pulled out a tube of drawings covered with dust over time. "Here," he said, handing it to Khanh Linh with trembling hands. "The final revised drawing that your father signed, asking to correct construction errors. I kept it for fifteen years, not having the courage to publish it, because I was afraid of Mr. Truong's power and money. But now, when I see you are brave enough to return, brave enough to face the truth, I think, it's time for me to do the right thing too."

Viet Hoang carefully opened the drawing tube and spread the yellowed paper over time on the small wooden table. Meticulous technical drawings appear, with Bach Vinh Son's familiar signature in the lower right corner, along with a handwritten note in red ink: "Urgent correction required before continuing construction — pipe diameter does not meet approved safety standards."

"This is irrefutable evidence," Viet Hoang said, his voice serious as he carefully examined every detail on the drawing. "The handwriting, the seal, the date are all clear. If compared with the drawing currently kept in official records, the difference will be ironclad proof that there has been a swap."

"Do you know anyone else, besides Mr. Truong, who may have participated in this file swapping?" Khanh Linh asked, trying to gather more information while Mr. Thinh was still willing to share.

Mr. Thinh pondered for a moment. "I think, in order to swap official records kept at the town's construction management department, there needs to be the help of someone with access to that archive," he said. "At that time, the head of the construction management department was a man named Dang Huu Loc, but he passed away a few years ago due to heart disease. Perhaps, that was a clue that was lost forever."

"But at least we have the original drawing to compare," Khanh Linh said, trying to find hope among the unfinished information. "This is the most important breakthrough we've had since we started investigating."

Mr. Thinh nodded, his eyes both relieved and worried. "I just hope that when you announce this, you will be really careful," he advised. "Ho Xuan Truong is now no longer simply an engineer, but a force with far-reaching influence in this town. He will not easily let this truth be exposed without fierce resistance."

Khanh Linh received the drawing tube with trembling hands, her tears could no longer be suppressed. “Thank you,” she said, her voice choked. "Thank you for keeping the most important piece of the truth, and for trusting me with it today."

When leaving Mr. Thinh's small house, Khanh Linh clutched the drawing tube in her hand as if it were the most precious treasure of her life. Viet Hoang walked beside her in silence, allowing her to have private space with her intensely surging emotions.

"I don't know how to describe this feeling," Khanh Linh said when they had walked a while, her voice still shaking. "For fifteen years, I've lived with the belief that perhaps I was the daughter of someone who caused the deaths of seventeen innocent people. Now, holding in my hands the evidence that my father was actually the only person who tried to prevent that disaster, I don't know whether to be more happy or hurt."

"Maybe both," Viet Hoang replied, his voice gentle. "You have the right to be both happy because the truth has finally been revealed, and painful at the thought of what your father had to endure unfairly in the last two years of his life."

Khanh Linh nodded, tears rolling down her cheeks. "I just wish my father could know that, in the end, his daughter did not give up and found the truth to exonerate him," she said, her voice choked up.

"I believe he is watching over you, and more proud of you than anything," Viet Hoang said, placing a comforting hand on her shoulder. "But there's still a long road ahead, Linh. We need to carefully plan our next step, to ensure this evidence is not destroyed or denied."