Shen Mingyue said laughingly: "Where are you talking about? Isn't it just to see if there is a murderer?"

"It's totally correct." Xu Jingnan praised, "This is the core point. If there is no second person on the scene, no matter how you explain it, Xiao Su can only decide the case by suicide. In other words, as long as we can find clues about this person's invisible human being, then all mysteries will be solved, and Xiao Su's cause of death will have another result."

"Based on the homicide consideration, our thinking needs to change. Assuming that this second person exists, where did he come from and where did he go? Where did Xiao Su himself come from and then die here?"

"The answer is simple, that is, the murderer and Xiao Su both entered the scene from the men's bathroom. After one of them killed Xiao Su, he hid from the men's bathroom, leaving no traces throughout the whole process."

Shen Mingyue looked at him straight and said nothing, Xu Jingnan quickly smiled as if she was concealed.

He then said, "If there is really no trace, my statement will be completely untenable. So I have a bold guess. In fact, there are certain traces, but we have not discovered them."

"First of all, a loose cement block appeared in a pit lattice in the men's bathroom. This cement block had been hit by external forces, so there was a hidden crack. It was impossible to detect it at that time, but after a month, the foot was finally exposed. I guessed it was caused by the squeeze of heavy objects, and it was elastic squeeze, leaving no damage left. This cement block was unexpectedly discovered by me. I thought about it for a long time, and the most reasonable explanation was that someone was wearing soft-soled shoes and repeatedly stepped on this part."

"The purpose of stepping on this position is nothing more than climbing the nearby vents. After understanding this, I basically finalized the function of the vents. So I went to check the vents repeatedly, looking at the dust distribution of different thicknesses, hey, there was indeed inspiration again."

"Can you go around?" Shen Mingyue said impatiently, but she didn't want to interrupt Xu Jingnan's thoughts.

Xu Jingnan chuckled and said, "This is still a mess, you can't figure it out for yourself, you may not understand it in the next life."

Shen Mingyue gave him a blank look, but she rarely said anything. She knew that Xu Jingnan was telling the truth.

Xu Jingnan smiled again: "Continue. I made an assumption from this that if the other party is a master, at least a master of counter-reconnaissance, it will inevitably clear the traces of various parts. This can be pushed back from the trampling part without footprints, and the footprints must have been wiped off by the other party with a soft cloth."

"Based on this assumption, the traces of the vent must have been removed. No one is so stupid, leaving such obvious wipe marks, let alone masters."

He suddenly sighed: "The reason why we were blinded at that time was because the vents had neither climbing wipe marks nor cleaned, so we fell into a logical circle and gave up doing useless work for the vents with thick gray."

"I believe that no living person on earth can pass through such a 50-centimeter-square vent like a flying fairy outside the sky without touching the dust around him." Xu Jingnan said very firmly, "It is impossible!"

This made Shen Mingyue confused: "What were you saying? Fifty centimeters are big enough. What if it was a child, step on the cement grid and jump out?"

"Impossible." Xu Jingnan said confidently.

"Why? There are so many children who can jump so hard now." Shen Mingyue disagreed.

Xu Jingnan analyzed: "This question is too simple, because I just measured the horizontal distance between the cement grid and the vent is more than 1 meter, and the vertical distance is more than 1 meter, and the vertical distance is more than 20 centimeters larger than the horizontal distance. There is no place to borrow force in the middle, and there is no trace of trampling. Do you think a child who is more than 1 meter tall can jump over? Maybe his head has not reached the vent... The only way is to climb."

"Oh." Shen Mingyue thought about it seriously. She didn't deliberately make trouble, so she quickly recognized Xu Jingnan's statement, "That's right."

"Hey, if it's an adult climbing, there's no trace? It's even more impossible."

Xu Jingnan looked at her with a smile and nodded: "That's right, it's naturally even more impossible. This is the key to this case."

Shen Mingyue agreed: "Yeah, if this person can climb in and then remove all the traces, then he will definitely not be able to do it when leaving. At least the trampling part that leverages force will definitely leave footprints. If this person is tied to the ventilator and turns around to clear the footprints, then there will definitely be traces on the ventilator. Unless this person is holding a stick or something, and a rag is tied to his head..."

She said impatiently: "Oh, it's over, it's over, my head is almost burned, and there will definitely be traces on the vents. Forget it, tell me the answer..."

Xu Jingnan looked like he wouldn't tell you, and Shen Mingyue shook his hand and gave him a big chestnut.

He touched his head helplessly, and this guy was too violent.

"It's not that I won't say it, it's just a bold guess, so I also want to hear your opinions." Xu Jingnan said a little aggrievedly.

"Say, what guess?" Shen Mingyue didn't want to think about it anymore, and she looked at Xu Jingnan coldly.

"That's right." Xu Jingnan said helplessly, "Assuming there are indeed traces on the vents and there are also wipe marks on the dust. So, besides cleaning the dust, are there any other ways to cover the traces?"

"I stood here and observed for more than half an hour, and an idea suddenly popped up in my head. Since subtraction doesn't work, what about addition?" He glanced at Shen Mingyue's reaction, and saw her cold eyes flashing directly, and he immediately didn't dare to ask again.

"I saw that the dust on the vent was unevenly distributed, so I thought of this addition. That is, this person carried a pack of dust in advance..." He smiled for no reason, "After the murderer tinted the vent, he stood outside the vent, took out the pack of dust, and then sprinkled it on the vent. Oh, it was inaccurate. It should have been blown on the vent, covering all the wipe marks, which caused an uneven thickness. The current criminal investigation technology is absolutely impossible to tell whether the dust originally existed on the vent or outside."

He added rigorously: "Of course, what I am talking about is not now, it is completely unjustified, because there are many new accumulations of dust, at least much thicker than before. After all, more than a month has passed, and the environment here is quite dirty. Any vision that surpasses ordinary people will never be able to find anything. It is just learning from one example and it just inspired the inspiration."

"It's a bit irritating." Shen Mingyue told the truth, but she also agreed from the bottom of her heart that this speculation might be valid.

She asked: "So, the murderer must exist, and he escaped through this vent."

"From the clues currently in hand, this is the only way to judge for the time being." Xu Jingnan said cautiously, "However, with such an assumption, at least the murderer cannot be completely ruled out. Comprehensive analysis, the possibility of Xiao Su committing suicide is getting lower and lower."

Shen Mingyue nodded: "Okay, before there are no other clues, we think this is the case." She jokingly said, "You can, boy!"

Xu Jingnan scratched his head: "It's a sloppy. As a member of Beiting, I can't be worthless."

"Hmph, just know." Shen Mingyue thought for a moment, "Then I will rest for one night and then go back to Dali. What about you? Will you continue to investigate?"

Xu Jingnan shook his head: "I am satisfied with such a little discovery. Besides, over the past month, there have been so many people coming in and out at the scene, so there is no breakthrough. If you continue to struggle, you can only waste your time. I'd better go back to the police station. It's still very busy there at the end of the year."

"Okay, there will be no future." Shen Mingyue waved her hand, turned around and left the alley.

Xu Jingnan looked at her blissful back, and somehow, a trace of warmth rippled in the corner of her eyes.
Chapter completed!