Sheriff Uncle, open the door quickly! I've come to solve a case!

Yan Qing paused, uttered a strange "Hmm?", and looked down at her legs: "Well, that's a long story."

The group talked as they slowly went upstairs.

"This happened once when the school organized a competition. I was in a car accident on the way. I survived, but I was left with aftereffects. However, it doesn't affect my ability to walk normally. Don't let my appearance fool you, I can still run and jump, hahaha."

Qin Qingzhou didn't laugh along; instead, a sharp glint appeared in her eyes.

Where were you the night before the school incident?

Yan Qing nodded: "Shouldn't you be sleeping at home?"

"Can anyone prove this?"

"No, what's wrong? Do you suspect me?"

Qin Qingzhou smiled politely: "No, it's just our police procedure."

"Okay." Yan Qing slowly walked to a classroom. This classroom had no walls, only a frosted glass panel.

Through the glass, you can see several students in white lab coats conducting experiments inside.

Yan Qing introduced them one by one: "These are all students from our school who participate in chemistry competitions. They spend most of their time in the chemistry lab preparing for the competitions. They are all very outstanding students."

Walking to the door of another classroom: "This one too, but I'm not the tutor. Teacher Bai, come out for a moment."

A female teacher looked over upon hearing the noise, said a few words to the student next to her, and then took off her gloves and came out.

She also twisted her ankle while walking?

"Your feet..."

Yan Qing chuckled and said, "Teacher Bai and I were in the same car before, and these are all aftereffects from that time."

Qin Qingzhou: "Besides you guys, has anyone else sprained their ankle?"

"No, what happened?"

"Just out of curiosity."

Ms. Bai was a little shy; she was a rather timid-looking female teacher: "Bai Yi."

"Ugh!" Bai Zhizhi suddenly began to struggle, her brows furrowed and her hand covering her nose.

Qin Qingzhou put her down, and she immediately scurried behind his legs, her eyes darting between the two teachers.

It smells awful...

Qin Qingzhou silently noted Bai Zhizhi's reaction, then took out her notebook and asked Bai Yi, "Where were you from 8 PM the night before last to 9 AM the next morning?"

Bai Yi replied shyly, "I'm at home."

"Can anyone prove this?"

"No……"

The adults were speaking in a language that Bai Zhizhi couldn't understand. After listening for a while, she got bored and started observing everything around her.

There are some really scary things everywhere here, like mannequins, organs preserved in formaldehyde, and so on.

But Bai Zhizhi wasn't scared at all; on the contrary, she found it very interesting. Taking advantage of Qin Qingzhou's inattention, the little guy ran away in a flash.

"Hide and seek, hide and seek," Bai Zhizhi hummed as she walked deeper into the building.

There were no students in class, and the lights were all off. A sliver of sunlight peeked through the closed curtains, making the whole space feel hazy and dim.

There was a small cabinet nearby, and Bai Zhizhi ran over and hid behind it.

"Zhi wants to play hide-and-seek with her older sister~"

"Is my sister going to hide here?"

Bai Zhizhi stared into the air; no one responded to her.

After Qin Qingzhou finished talking, he turned around and found that Bai Zhizhi was gone.

The two teachers were in a hurry to go back to class, so after Qin Qingzhou parted ways with them, she started looking for Bai Zhizhi.

Finally, they found Bai Zhizhi laughing and joking next to a small cabinet deep inside the building.

"Wow! Zhizhi has been spotted by her uncle! Run!" Bai Zhizhi cried out in surprise and ran away quickly, hiding next to another cabinet.

"What are you doing? Don't wander off." Qin Qingzhou followed him patiently.

"Zhi is playing hide-and-seek."

"Go back to playing games..." Qin Qingzhou abruptly stopped.

hide and seek?

Bai Zhizhi also mentioned playing hide-and-seek last night.

"Zhizhi is learning to play hide-and-seek with the young lady. She's played hide-and-seek here before too."

Qin Qingzhou's breath hitched, and she finally understood Bai Zhizhi's meaning: "You mean, Xu Shuang hid here?"

"Mmm!" Bai Zhizhi hurriedly got up and pulled Qin Qingzhou to squat down by the cabinet.

Qin Qingzhou was tall and strong, and the cabinet couldn't hide him at all.

"Uncle, hide quickly, the big bad guy will catch you!"

Qin Qingzhou felt ice-cold all over. If what Bai Zhizhi said was true, Xu Shuang had hidden here to avoid someone, then her death must have been because that person discovered her.

How did she end up being taken to the top floor?

What did Xu Shuang discover when she came here?

He immediately called the police officers waiting downstairs: "Bring Afu up."

The chemistry class was forced to stop, and the students were herded downstairs with cries of distress.

The police officer let Afu smell Xu Shuang's clothes, and Afu barked and started sniffing them on the spot.

A few minutes later, Afu started yelling at a cabinet.

Qin Qingzhou walked over and opened the cabinet, where a cell phone lay quietly.

found it!

Xu Shuang did indeed hide here!

"Immediately take control of Yan Qing and Bai Yi! Seal off the laboratory building!"

Both chemistry teachers were taken back for questioning, and the case made great progress.

With Xu Shuang's phone, Qin Qingzhou finally figured out what those accounts were.

The police officers in the team took some time to hold a meeting and organize all the existing evidence.

That was three days before the incident; Xu Shuang had proactively added one of the accounts.

[Teacher, something's strange about the school's science building. When I was feeding the kitten, it went up to the fifth floor and then disappeared. I can't find it anywhere.]

[It probably went into one of the classrooms. Don't bring the kitten in again; there are many valuables here.]

[Is that so? Thank you, teacher.]

One day later.

[Teacher, I still feel something's not right. I went to the fifth floor and looked around; it seems there's a space we don't know about.]

Don't go there anymore. I've already contacted the police, and they will investigate. Just focus on your studies.

Then on that day, several people added Xu Shuang on WeChat. They all claimed to be police officers and told Xu Shuang not to cause trouble for the police and not to go to the laboratory building anymore.

Qin Qingzhou's brows furrowed more and more as he watched.

Xu Shuang left a message for that teacher on the day of the incident.

[Teacher, I heard a strange noise during chemistry class this morning. It seemed to be coming from a hidden room. Is it really okay?]

It wasn't until the afternoon that the teacher left a message for Xu Shuang.

[You're right, it is a bit strange. How about this, come to the lab building during your evening self-study session, and we'll go take a look together.]

[Teacher, I've arrived.]

[Teacher, where are you?]

There were really strange noises coming from that room; I was a little scared.

There has been no further news about Xu Shuang since.

After everyone finished reading, they fell into deep thought.

"Did the teacher kill Xu Shuang?" Li Ku asked incredulously.

Zhao Tai nodded: "Moreover, according to the chat logs, there are hidden rooms in the laboratory building, where something must have been going on that Xu Shuang discovered, leading to murder."

Both teachers were taken to the police station. On the surveillance footage, the two teachers sat quietly in the torture chair, and both of them looked so kind.

Li Ku: "The murderer must be one of these two."

Li Ku looked at Qin Qingzhou, who was deep in thought: "Captain Qin, what do you think? Should we let Bai Zhizhi take a look?"

Qin Qingzhou withdrew her gaze, got up, and left.

"Need not."

"I already know who the killer is."