Everyone arrived at the supermarket and pulled up the surveillance footage, but they unexpectedly found out that the monitored field of view just avoided the location of the incident and they could only see the road in front of the door.

Lin Qiupu furrowed his brows. "Could it be so coincidental? The only camera didn’t capture anything?"

"I think that someone deliberately did it." Chen Shi borrowed a step ladder from the supermarket and went out with Lin Dongxue. He propped up the ladder and got Lin Dongxue to climb up and have a look while he supported it from below.

Lin Dongxue checked around the area. "A little of the dust on the camera has been wiped off." As she spoke, she took photos of it using her phone.

Chen Shi looked around, and noticed that a fruit shop across the street also had a security camera. The police all went over to watch the footage. It took half an hour for them to discover someone in the surveillance footage sneaking to the door of the supermarket late at night, before pulling out a foldable hook and moving the security camera a little.

The time indicated was August 6th, before the murder.

The person captured in the video was wearing a black sweater and was wrapped up tightly. The resolution was too poor for them to even figure out whether the person was a man or a woman.

There was no doubt that the person was the murderer. He was unexpectedly meticulous and had surveyed the place where he would abandon the corpse in advance to eliminate potential risks. Of course, if the murderer hadn’t been so cautious, it would have been impossible for them to remain at large for six consecutive years.

Chen Shi thought out loud, "Why did they do this?"

Lin Dongxue went to the supermarket to buy two bottles of beverages and handed one of them to Chen Shi. "Isn't that simple? They didn’t want to be filmed."

"But didn't the other camera film them? It shows that it’s not themselves that they didn't want to be captured, but something else..."

"Something else?"

"The car they were driving, or the time of abandonment. Taking this into account indicates that they predicted that the police would investigate their alibi. So, it seems that they’re within our field of view..." Chen Shi muttered to himself. His logical brain was working at full speed. He suddenly looked up. "Remember to copy the surveillance footage from the supermarket!"

Lin Qiupu replied, "Both the supermarket’s and fruit shop’s footages have already been copied."

"Old Peng, Old Peng, accompany me to the scene again."

Chen Shi hustled across the road. Lin Qiupu complained, “Exactly who is the captain around here?" Lin Dongxue said with a smile, "Seeing him so excited, he must have an idea!"

Back at the crime scene, Chen Shi observed the body from all angles, as if he was an artist examining an exquisite piece of art. He opened the deceased's eyelids and moved her arms in order to reconfirm the time of death.

Peng Sijue said, "Don't look anymore. The time of death is around 9:00 on the 7th. It couldn’t be wrong."

"What about the time that the corpse was abandoned?"

"The abandonment time..."

"Is there a way to figure out when it was abandoned?"

"That’s very difficult. We can start with the microbes and insects at the scene, but..."

"That’s not accurate enough. I need it to be more precise, with the margin of error within one hour."

Everyone's face was blank. This was really a difficult problem. Chen Shi stared at the body in thought for as long as half an hour. He kept muttering to himself. There was a policeman smoking a cigarette at the side and Chen Shi stopped in front of him and glanced at him.

The policeman was too embarrassed to keep smoking and put the cigarette out. However, Chen Shi took a deep breath of second-hand smoke to take in a little nicotine to rev up his brain.

Peng Sijue said, "Don't look anymore. We have to take the body back for the autopsy."

"Wait, wait..." Chen Shi squatted down besides the corpse and crushed some salt granules with his fingers. He flopped down on the ground to observe the surface, and suddenly smiled. "The ground’s surface is soil!"

"So what if it’s soil?"

"Salt touches blood, dissolves, and seeps into the soil... Old Peng, can you use this as a reference to calculate the time when the corpse was abandoned?"

Peng Sijue thought about it for a while and said, "We need to conduct a set of experiments to compare it."

"Then do it. Take away the soil from the scene. The soil that’s stained with blood and the soil that isn’t. I want them all."

Peng Sijue immediately ordered his subordinates to head over and start the project. In order to not destroy the original structure of the soil layer, they bought some lunch boxes from a nearby convenience store and shoveled the soil layers neatly into them.

Anxious to get the result, Chen Shi left directly with Peng Sijue in his car, leaving Lin Dongxue behind.

Lin Qiupu smiled bitterly. "This guy really embodies the saying ‘nothing short of obsession will bring you success’[1]... I’ll send you home!"

That night, the members of the forensics department worked overtime, while monitored by Chen Shi, doing the salt granules permeation experiments. They were busy until 10:00 in the evening. Of course, for the results, they had to wait till tomorrow morning.

Chen Shi sat there to supervise and think about the whole case. He suddenly came up with the sentence, "Old Peng, can you drink alcohol while on antidepressants?"

"It depends on which kind."

"Paroxetine."

Peng Sijue checked the ingredients of the medication on his computer. "If this medication is taken with alcohol, the person’s blood pressure will rise, accompanied by stomach cramps. The negative side-effects are relatively severe.”

"Would you die?"

"It depends on the dosage, but even if you drank alcohol with the typical dosage, you wouldn’t die. At most, you’d suffer terribly."

"Oh... The doctor should tell you not to drink, right?"

"This is beyond the limits of my understanding."

"'I don't know' was said in such a roundabout way..." Chen Shi smiled. "Oh, has the morning autopsy results come out yet?"

Peng Sijue threw a report at him, and Chen Shi skimmed it. "The internal organs were in pieces and the stomach pouch was missing? There were baked-brick fragments found on the back of the head?"

Peng Sijue said, "I think your deduction at the scene may be right. The murderer opened up the deceased's abdomen to look for something. The entire abdominal cavity had been messed with. It seems that the murderer doesn’t have professional anatomical knowledge and took the entire stomach away."

"If that’s the case, the deceased might have swallowed something before her death. It may be an important piece of evidence... Do you think that the two victims were killed by one person?"

"Tonight’s body hasn’t been dissected yet, so it’s not clear. Although the cause of death was different for the victim found in the morning, the other details are all very similar. Because the bodies were all dissected by me in previous years, I’m quite familiar with everything."

Chen Shi glanced at the report, "Then Cai Yating was an unplanned murder. The murderer took her stomach after killing her, and then put her in a red dress to “dress her up"... What did Cai Yating swallow? Can you test for that?"

"During the autopsy, we found that the esophagus wasn’t damaged. It seems that it wasn’t anything too big. However, if you want to test what it was, it’s quite a lot of work and it isn’t easy to get results. It’s likely that we won’t get any results even after a few days. Are you sure?”

"Forget it, there’s no need... She chose to swallow it before she died, indicating that the item isn’t easy to damage and that it’s relatively small."

"Could it be... A USB flash drive or a memory card for a mobile phone?"

"Well, there’s that possibility, but unfortunately we probably wouldn't be able to see it... Oh right, if that’s the case, it shows that Cai Yating had been secretly investigating the murderer and knew his identity. That’s why she was killed."

"Actually, Captain Lin is also checking Cai Yating's lead today. Her profession is a newspaper reporter. We found information about the Qixi Festival serial murder cases on the computer in her house. She’s indeed been tracking these cases."

Chen Shi sighed with sympathy, "Poor girl, perhaps she already knew the truth, but she never had a chance to tell anyone."

1. No excellence is possible without fanatical absorption in one’s work.