In the monitoring room of the police station, the controller on the doorknob scanned Xu Chengyan's fingerprints and confirmed his identity before opening the door.

Walking into the room, there are dozens of monitors neatly arranged, and each portrait controls the key positions of the police station, especially the underground parking lot.

"Who are you?" the management of the monitoring room heard the noise here, strode over, frowned, and looked at the two people at the door suspiciously.

"Hello, I'm the leader of the serious crime team, Xu Chengyan. The one next to me is the forensic doctor of the forensic team, Qiu Lan. Xu Chengyan took out the police card in his bag and checked it for the management to confirm the identities of himself and Qiu Lan.

"Officer Xu, Doctor Qiu, hello, I am the person in charge of the monitoring room. After checking the police ID, the manager raised his eyebrows and asked softly, "It's so late today, I don't know what you are doing here?"

Xu Chengyan, who looked solemn, looked at the monitor screen behind him, his lips pursed into a straight line, "When I was in the underground parking lot just now, Dr. Qiu heard very strange footsteps, I suspect it is related to the person who intimidated her before, so come and take a look." ”

"Have you been guarded here all along?" he said, glancing at the person sitting in front of the video portrait looking at the screen.

Hearing his words, the manager nodded slightly, "Yes, this is the monitoring and control center of the entire police station, so we have people here twenty-four hours a day, and weekends are no exception." ”

"Then did you see anything unusual in the underground parking lot in the video just now?" Qiu Lan bit her red lip lightly, raised her eyebrows uneasily, and hurriedly spoke.

"Parking lot?" the manager lowered his eyes and pondered for a moment, "I don't have any impression of this, but it should be nothing out of the ordinary, otherwise our people will definitely go down to check it out." ”

"That's right. Xu Chengyan frowned indifferently, and glanced at the person beside him worriedly, "Then can you please show us the surveillance video from ten to twenty minutes ago?"

In the toilet of the autopsy room before, Qiu Lan had already been intimidated once, but she didn't find any directional clues that time. But unexpectedly, today she heard sneaky footsteps in the parking lot again.

No matter what the situation of this voice is, Xu Chengyan will investigate it clearly and will not let go of any clues.

Since this person can haunt the police station, the target of intimidation every time is Qiu Lan, and if he doesn't investigate it as soon as possible, maybe there will be a greater danger hidden in the future.

"Yes, Officer Xu, Doctor Qiu, come with me. The person in charge of the monitoring room replied and led them into a small office behind the huge surveillance system.

He turned on a computer on his desk, entered some information into the computer, and finally found some of the programs, "These are the monitoring of the entire parking lot from Area A to Area E." ”

"Because the underground parking lot is an important location, and it is very large, it is divided into five areas in total, and there are about 30 monitors, and it may be time-consuming to look at them one by one. The manager gently flicked his lips and crossed his hands over his chest, giving them a brief message.

"I heard it in Zone C, near the second elevator of the police station. Qiu Lan twisted her fingers, thinking carefully about the situation just now, "That voice is very close to me. ”

"There are about 20 decibels, and if you calculate the distance, with me as the central point, it should be between 10 and 15 meters. ”

Listening to her words, the management nodded, his eyes wandered, and he turned around and clicked on the two video images on the screen, "Doctor Qiu, according to your words, I think the surveillance cameras of C3 and C5 should be able to capture some content." ”

"The computer is connected to the monitoring system, so you can see the real-time situation and you can play it backwards. The manager moved the mouse and dragged the progress bar below to the first thirty minutes.

After pressing twice as fast forward, all three people in the office began to stare intently at the images on their computer screens.

About two minutes later, a woman's figure appeared in an area in the lower right corner.

"It's just me. Qiu Lan pursed her red lips and looked at the situation carefully, "Looking at the way I looked at that time, I shouldn't have heard anything yet." ”

After seeing Qiu Lan's figure appear in the surveillance video, the management staff switched the speed to 0.5 times, so that it was easy to see the two surveillance screens.

"You turned around, you must have heard a voice. Xu Chengyan looked at every corner of the surveillance seriously, and the expression on his face gradually froze, "However, we can't see anyone else here." ”

"Yes, I didn't see it when I turned around. Qiu Lan looked at the computer screen with a heavy face, frowning slightly, "However, it should have been less than a minute, and I heard a voice behind me again." ”

Sure enough, in the surveillance video at 0.5 times the speed, forty-six seconds later, Qiu Lan in the image turned around vigilantly, and the expression on her face became colder.

The next thing is her defensive against the wall, and then the appearance of Xu Chengyan.

During this time, she didn't hear anything, maybe because someone else was there, and the person who made the sound left, or maybe she didn't have time to pay attention.

In the office of the monitoring room, Xu Chengyan and Qiu Lan looked at each other solemnly.

"Officer Xu, Doctor Qiu, this is the surveillance video during this time, but it seems that no one else has appeared except for you. The manager pressed the pause button, turned to look at them, and spoke slowly.

"Yes, but that voice appeared twice, how could you not see a human figure?" Qiu Lan sighed lightly, staring meaningfully at the computer screen.

"Doctor Qiu, do you think it's possible to mishear?" Xu Chengyan pursed his thin lips and asked softly, "There have been a series of cases recently, you must be also tired, could it be auditory hallucinations?"

Before Qiu Lan joined the forensic team, he had investigated a suicide case, and in that case, one witness kept saying that he heard shouts for help at the scene of the crime.

However, in the end, after the confirmation of the forensic department and the accurate judgment of the forensic team, it was found that the witness was overworked, which caused temporary damage to some functional parts of the brain, resulting in auditory hallucinations.

In this case at that time, other evidence pointed to the suicide of the deceased, but because of a hallucination of this witness, the entire serious crime team investigated for a whole month without results.

So Xu Chengyan has always remembered to ask for this case.

"No, it won't. Qiu Lan shook her head, her eyes fixed on the surveillance screen, "Officer Xu, although there have been a lot of things recently, I have ensured a good night's sleep, and I shouldn't have auditory hallucinations." ”

"What's more, how could I have two auditory hallucinations in such a short period of time? ”