Yu Xinxin's words jolted Xiao Lou awake—she heard a distinct cough, which meant that Liu Yuming wasn't the only one who got up to use the bathroom in the middle of the night!
Xiao Lou smiled at her and continued, "Xin Xin, can you be sure when you heard the cough?"
Yu Xinxin tilted her head and thought for a moment, then said, "It should be 3:10. I went to the toilet and returned to my seat. I even looked up at the time on the carriage screen."
Xiao Lou quickly picked up a pen and paper and wrote down this crucial information.
He followed up with, "And then? Did you hear or see anything else?"
Yu Xinxin said, "The old lady seemed to be very ill. She coughed for a while, and then her voice got farther and farther away until I couldn't hear it anymore. But strangely, after the old lady walked away, there seemed to be a dark figure in the dining car walking towards car number 6."
Xiao Lou asked gently, "How tall was that dark figure? Was he fat or thin? Do you remember?"
Yu Xinxin thought for a few seconds and said, "He should be quite thin, definitely not fat! I didn't see how tall he was."
"And then?" Xiao Lou asked, looking at her. "Did anyone else go to the bathroom?"
"Yes! A few minutes later, around 3:30, I saw the lights come on in carriage number 6. The light was very bright, and there were strange noises coming from the trash cans."
Xiao Lou was startled. The obvious light meant that Liu Yuming must have taken a rechargeable light to the restroom; he was the only one in the group with a rechargeable light.
During the previous questioning, Liu Yuming said he went to the toilet at 3:00 AM, but Little Girl said it was 3:30 AM, which is a half-hour difference—children don't lie, so it's obvious that Liu Yuming is lying!
"Uncle, are there rats in the carriage?" Little Girl asked earnestly, tilting her head up.
"There were no rats in the car. Someone probably bumped into the trash can by accident." Xiao Lou smiled slightly and asked softly, "How long did that sound last?"
"It only took a few seconds," Yu Xinxin said with a smile. "I even thought to myself, maybe a rat was rummaging through the trash can for food, and someone got up in the middle of the night to catch it!"
Xiao Lou patted the child's head and asked, "Besides the sound, what else did you see?"
Yu Xinxin said, "Shortly after the sound of the trash can was heard, the red lights on both restrooms in carriage number 6 turned on."
On the high-speed train, there are restroom signs on the ceiling of the carriages. When no one is in the restroom, the light is green (no one is there). When someone enters the restroom and locks the door, the light turns red (someone is there).
With many passengers in the carriage, this arrangement is designed to help passengers determine whether the restrooms are available. If you want to use the restroom and see that both restrooms on the top of the carriage are occupied, you can wait a moment until the person leaves before going to the restroom.
Unexpectedly, this simple light prompt became a key clue in the case!
Little Girl said that after the lights came on, strange noises came from the trash cans, and then both restrooms were marked as "occupied." This means that when Liu Yuming was using the restroom, someone else entered the restroom opposite him.
There were two people in the restroom at the time, a very obvious point of suspicion, yet Liu Yuming made no mention of it.
Xiao Lou then asked, "Both restrooms have red lights, which one turns green first?"
Little Girl said, "The light on the left side of the restroom turned green quickly, and the old man with the light walked away. The light on the right side remained red for a long time, probably because someone had diarrhea!"
Upon hearing this, Yu Xinxin's mother's expression became tense: "Did something happen to car number 6? Why have you been asking me about my daughter's situation last night?"
Xiao Lou gave her a reassuring look and said, "It's nothing serious. An elderly person lost some valuable jewelry, and we need to investigate carefully to find the thief." He looked at the child and said gently, "Xin Xin hates thieves, right? So, you should tell Uncle everything you saw and heard, okay?"
Xiao Lou was quite adept at charming children, and with his kind and gentle smile, little Yu Xinxin really liked this flight attendant uncle. To help catch the thief, she eagerly shared everything she knew—
"I couldn't sleep after using the restroom last night. Everyone else in the carriage was asleep, so I sat in my seat and looked at the stars outside."
"After the person with the lamp left, there was a sudden meteor shower outside the window, it was so beautiful! I kept watching the meteor shower, and after about ten minutes, I heard hurried footsteps from car number 6. I didn't see clearly, but the person walked to the vicinity of the dining car, didn't go to the toilet, and suddenly turned back. Immediately afterward, the toilet door on the right opened, and the light turned green."
"It was around 3:40 a.m., and there were two coughs in the carriage. Then, I was very sleepy and fell asleep."
Xiao Lou wrote down her answer word for word with lightning speed.
Yu Xinxin looked at him curiously and asked, "Uncle, will what I'm saying be of any help?"
Xiao Lou smiled gently: "Xin Xin is great. What you said is very useful. We will definitely catch the thief."
Yu Xinxin smiled, her eyes crinkling: "That's good!"
She didn't know what happened after that, as she was asleep. When Xiao Lou couldn't get any more information out of her, he had Yu Xinxin's mother carry her home. Yu Xinxin waved to Xiao Lou, "Goodbye, Uncle!"
Xiao Lou said goodbye to the little girl.
He turned and walked towards carriage number 6, but halfway there, Zhou Zheng from row 8 suddenly stopped him with a grim expression and whispered in his ear, "Is someone dead in carriage number 6?"
Xiao Lou turned around in surprise, lowering her voice: "How did you know?"
Zhou Zheng took out his phone and showed Xiao Lou a WeChat message from his girlfriend, Mo Jiaran.
There was a long list of WeChat messages on my phone: "An elderly person died in carriage 6. The train attendant locked the carriage door and wouldn't let anyone out. They just checked all the passengers' luggage one by one. It was terrifying!"
Zhou Zheng: "What's going on? How could someone die?"
Mo Jiaran: "I don't know. I heard people outside talking about it, saying it was a sudden heart attack or something. The senior citizen tour group is very nervous. I don't want to stay in carriage 6 anymore. Can you come and pick me up and take me back?!"
Zhou Zheng comforted her, "Don't worry, let me ask the flight attendant."
He put his phone away and asked Xiao Lou in a low voice, "Could you let my girlfriend go back to carriage number 4? She's all alone there, feeling scared. I'm worried about her."
Xiao Lou said, "I'm sorry, we're still investigating and can't let anyone leave for the time being. Don't tell anyone yet. Send her a text message and tell her to stay in her room and that this has nothing to do with her. We won't make things difficult for her."
Zhou Zheng frowned and said, "Alright."
He had a headache and was worried that he wouldn't be able to persuade the young lady. Xiao Lou was also afraid that the young lady would make a scene, so he went to carriage 6 and went to Mo Jiaran's room to comfort her, saying, "Miss Mo, don't worry, our investigation will be completed soon. If you want to go back to carriage 4, we won't stop you."
Mo Jiaran nodded, his face pale.
Xiao Lou turned and went to the attendant's office in car number 6. Yu Hanjiang was frowning as he looked at the notebook filled with testimonies.
Their eyes met, and Yu Hanjiang quickly stood up and said, " Professor Xiao, please have a seat."
Xiao Lou smiled and shook his head: "It's alright, Captain Yu, please sit down. I have Yu Xinxin's testimony here, let me show it to you."
He closed the office door behind him, leaned against the desk, and picked up Yu Hanjiang's interrogation transcript of Old Mrs. Mei and looked at it carefully.
The office was quiet, and the two were looking at the results of each other's inquiries.
This case is far more complex than I imagined.
A few seconds later, Yu Hanjiang, who was sitting in his seat, suddenly picked up a pen and drew a floor plan of the carriage on his notebook.
He pointed to the diagram and explained, "The dining car is in the middle, with carriage number 6 on the left and carriage number 4 on the right. Since the dining car doesn't have a restroom, it shares two restrooms with carriage number 6, which are located at the end closest to carriage number 4. Yu Xinxin's seat is very close to the dining car, so she can clearly see the light indicators on the top of the carriage."
Yu Hanjiang then drew the seating arrangement of the elderly group: "Rooms 1, 2, and 3 are all quite far from the restrooms. They need to walk through the entire carriage to reach the restrooms near the dining car."
Xiao Lou looked at the testimony with some doubt and said, "According to Xin Xin's description, she heard a distinct cough. Could that cough be that of Grandma Mei? You wrote in the record that she had obvious asthma and would cough uncontrollably when answering questions."
Yu Hanjiang nodded and said, "It should be her. The murderer committed the crime in the middle of the night, so it's impossible for her to make too much noise for anyone to hear. What if her cough woke up people in other carriages, and they opened their doors to check the situation and were caught in the act? So, there's only one explanation—Grandma Mei couldn't control her cough. She did get up to go to the toilet around 3 a.m.."
Yu Hanjiang decisively picked up a ballpoint pen and, based on Yu Xinxin's testimony, pieced together a timeline—
"At 2:00, Li Zhemin finished playing cards with the three old men in the same room and went to sleep together."
At 3:10, Grandma Mei got up to use the restroom and coughed. Yu Xinxin also saw a figure appear in the restaurant.
"At 3:30, Liu Yuming went to the toilet with a flashlight. The sound of a mouse came from the trash can and lasted for a few seconds. Another person went into the toilet across the street, and both toilets turned into red lights indicating that they were occupied."
"Around 3:40, someone intended to go to the restroom, but turned back halfway. At that moment, the person from the restroom across the way finally came out, and coughing sounds came from the carriage again. Yu Xinxin then fell asleep."
The timeline is very well organized.
However, with so many people going to the restroom one after another, Xiao Lou couldn't help but press his temples, feeling a headache coming on—coughing, lights, sounds near the trash cans, hurried footsteps fading into the distance…
It seems that there was a lot of undercurrents in carriage number 6 last night!
Yu Hanjiang looked at the timeline organized in his notebook, stroked his chin, and fell into deep thought.
After a moment, he began to analyze the clues one by one: "At 3:10, a figure appeared in the restaurant when the old lady went to the toilet. One possibility is that the murderer was preparing to commit the crime when he suddenly heard the old lady coughing. In order to avoid being discovered by the old lady, he slipped away and hid in the restaurant."
Xiao Lou thought this guess was reasonable; otherwise, why would someone go to a restaurant in the middle of the night?
He agreed, saying, "That makes sense. If it's just a simple matter of going to the restroom, it wouldn't matter if we bumped into Grandma Mei. There's no need to hide in the restaurant unless someone has something to hide. It seems that the person who hid in the restaurant is very likely the murderer."
Yu Hanjiang pointed to the Third of a Kind timeline and said, " Liu Yuming is lying. He deliberately confused the time, and the reason he gave for looking for the watch was also made up—Xin Xin said that there was a strange sound coming from the trash can, and it only lasted for a few seconds. It's impossible for him to find the watch in a few seconds."
Xiao Lou nodded: "That's right, in a few seconds, it's more likely that someone accidentally bumped into the trash can in the chaos?"
The person might be the murderer who was hiding in the restaurant earlier. They wanted to go back, but then ran into Liu Yuming, so they hurriedly hid in the restroom.
Yu Hanjiang said, "At 3:30, when Liu Yuming went to the toilet, the toilet across the street also turned red. Your analysis is very reasonable—the person in the restaurant wanted to return to car number 6, but bumped into Liu Yuming and had to hide in the toilet. He stayed in the toilet until 3:40."
Yu Hanjiang circled several key points on the notebook with his pen: "3:40, this time is crucial, three people appeared at the same time - the first is the person hiding in the toilet, who felt that it was safe outside and finally came out; another is the person who was going to the toilet but turned back halfway, probably because he saw someone suddenly come out of the toilet and hurriedly turned around and ran away; and then there is Grandma Mei, who got up in the middle of the night and coughed."
Xiao Lou frowned and thought for a moment, then said, " Li Zhemin's time of death should be after 3:40. So, in the half hour between 3:10 and 3:40, many people in the senior group got up to use the restroom, which caused the murderer to keep encountering other people... He first hid in the restaurant, then in the restroom across the street, but when he came out of the restroom for the last time, could he have run into Grandma Mei?"
Xiao Lou pointed out a key point.
The person who keeps hiding is very likely the murderer.
Otherwise, there's no way to explain why he repeatedly avoided acquaintances in the elderly group.
The last time, Grandma Mei got up in the middle of the night, but Xin Xin was asleep and didn't see what happened. Did the murderer manage to escape, or did he finally give in and get discovered by the old lady?
If it's the latter, then Grandma Mei is definitely protecting the murderer.
Xiao Lou reviewed the testimonies of these people again and said, "Grandma Mei and Niu Dapeng lived in the same room. Niu Dapeng knew that Liu Yuming next door went to the toilet with a light on, so it's impossible that he didn't know that Grandma Mei had also gone to the toilet— Niu Dapeng was deliberately hiding it."
Yu Hanjiang said, " Liu Yuming is also lying by confusing the time he got up at night and making up the excuse that he went to the trash can to look for his watch."
Xiao Lou said, " Zheng Weiguo's claim that he found the IOU in the deceased's pocket early in the morning is clearly a lie."
Both of them simultaneously pinched their temples, looking troubled.
—Everyone is lying.
If Yu Xinxin hadn't reorganized the timeline, the two of them would have been completely confused by the lies of this group of people.
Yu Hanjiang said helplessly, "It seems very likely that Grandma Mei is protecting the murderer. Li Zhemin has very poor interpersonal relationships."
Xiao Lou took a deep breath, reorganized her thoughts, and said, "For now, Liu Yuming and Grandma Mei can be ruled out. Their appearance alerted the murderer, causing them to hide. Therefore, the murderer is likely to be either Niu Dapeng or Zheng Weiguo. Niu Dapeng is tall and fat. Xin Xin said that the figure was thinner, so Zheng Weiguo is more likely?"
Zheng Weiguo was heavily in debt from gambling. He stole the IOU and committed murder, so he had a strong motive and plenty of time to do so.
But why did he admit to stealing the IOU? Since the IOU has been destroyed, if he doesn't admit it, no one can find evidence...
Xiao Lou felt that something was wrong.
Just then, Yu Hanjiang suddenly narrowed his eyes: "I think the person who went to the toilet at 3:40 in the morning and turned back halfway is Zheng Weiguo."
Xiao Lou was somewhat surprised: "Why do you say that?"
Yu Hanjiang looked at Xiao Lou and whispered his analysis: "We can deduce it like this: at 3:30, Liu Yuming took the lamp to the toilet. At that time, Zheng Weiguo, who shared the room with him, was probably awake. He found that his roommate had gone to the toilet alone while the other two were asleep. So he climbed off the bed and took the opportunity to take the IOU from Li Zhemin's pocket."
" Liu Yuming went to the toilet and quickly came back to sleep. Zheng Weiguo listened to the noise in the room, and after Liu Yuming fell asleep, he secretly got up, intending to go to the toilet to flush away the IOU with water."
The clues to the IOU have been nowhere to be found.
High-speed trains have fully enclosed carriages with windows that cannot be opened, so trash cans are easily discovered by train staff; burning... High-speed trains are completely smoke-free and fire-free, and any fire will directly trigger the smoke alarm.
Hiding the IOU on your person or in your bag isn't safe either. If you want to destroy it completely, there's only one best way—the toilet!
He tore the note into pieces, threw it into the toilet, and flushed it down, thus completely destroying the evidence.
Unexpectedly, when he got up to go to the toilet, someone suddenly came out from the other side. Zheng Weiguo, feeling guilty, hurriedly turned back and, just as Captain Yu had predicted, swallowed the IOU.
Captain Yu's speculation is logically sound; otherwise, who would go to the toilet in the middle of the night, only to turn back halfway?
Therefore, it seems unlikely that Zheng Weiguo is the murderer; he only stole the IOU and did not kill anyone. The murderer is the person who hid in the restaurant earlier, then hid in the restroom, and came out of the restroom at 3:40.
It's not Zheng Weiguo, not Liu Yuming, and not Grandma Mei.
Xiao Lou said, "It seems to be Niu Dapeng? But... Xin Xin said the shadowy figure is very thin, while Niu Dapeng is tall and fat."
At this point, his eyes suddenly lit up: "It seems there's one more person we've been overlooking!"
Yu Hanjiang nodded solemnly and said in a low voice, "The first one we eliminated was Aunt Shu Ping."
Shu Ping's testimony flashed through Xiao Lou's mind—
She introduced her daughter to Li Zhemin's son, but Li Zhemin scolded her daughter for being ill-mannered. Enraged, she stole Li Zhemin's insulin, intending to teach him a lesson. At the time, the two men believed that if she were the murderer, there would be no need to steal the insulin, and since her daughter had only been scolded, her motive was insufficient, so they ruled her out.
Her testimony
It seems reasonable and can reduce suspicion against oneself.
But there is a key point.
Yu Hanjiang said coldly, "No one can testify to her testimony."
Niu Dapeng and Li Zhemin are vying for the manager's position; their long-standing feud is something everyone can attest to.
Liu Yuming has seen the IOU and can serve as a witness regarding Zheng Weiguo's theft of the IOU.
Most people know that Liu Yuming's beloved first love was stolen away by Li Zhemin, and even Grandma Mei can testify to this.
But who can testify to what Shu Ping said?
Only the deceased Li Zhemin knows the truth!
She claimed that Li Zhemin insulted her daughter, saying she was ill-mannered, and that she couldn't stand it and wanted to retaliate. She only mentioned her conflict with Li Zhemin, but there was no third party to witness it.
In fact, from the very begi
nning, Shu Ping's testimony was the least credible!