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

Xu Shuang stood downstairs in the laboratory building, looking down as she sent a message to her teacher.

[Teacher, I've arrived.]

[Teacher, where are you?]

It's evening self-study time now, and the laboratory building is completely dark.

Xu Shuang was a little scared. She was dressed lightly for the night, and a chill crept into her body.

She noticed something was wrong with the laboratory building a few days ago. It started when the stray cat she fed wandered into the building that day, acting very mischievously.

Xu Shuang knew that there were many valuables in the laboratory building, so she planned to bring the cat back as soon as possible.

As a result, the stray cat disappeared on the fifth floor. While searching for the kitten, she heard strange noises coming from the classroom where they usually did chemistry experiments.

There were sounds of metal clashing, friction of unidentified objects, and even strange smells.

Is anyone still here at this time?

Could it be a ghost?

She looked around somewhat frightened; everywhere she looked, there was equipment that exuded a terrifying aura.

Xu Shuang was a little scared, so she quickly found the cat and left.

Xu Shuang was standing here tonight because she felt something was wrong and came here alone after asking her teacher for help.

"There are no ghosts in the world," Xu Shuang comforted herself.

The teacher was late, so she gritted her teeth and went upstairs alone.

The fifth floor was pitch black. According to my memory, the strange noise came from the chemistry lab. There were no lights on outside at the time, so the chemistry lab should have a hidden door.

Upon entering the chemistry classroom, she felt around the perimeter and, sure enough, found a crack that wasn't part of the wall.

There was a hidden compartment next to it. Pressing the button made the hidden door open with a "click," revealing an operating room inside.

"How could this be..." She covered her mouth, too shocked to speak.

Could it be that someone was performing surgery inside when the strange noise occurred earlier?

Why would there be such a place on a school campus?

She quickly took out her phone and sent a message to the teacher.

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

Drip!

The WeChat ringtone sounded, particularly noticeable in the quiet night.

Xu Shuang was startled and subconsciously turned off her phone. The faint screen flickered in the classroom.

It was a message from the teacher.

[Quick, hide! I saw a strange person!]

[Wait for me to find you.]

Xu Shuang was terrified and could only run to the back of the building and hide in a closet.

Slowly, she heard a sound like dragging footsteps, one after another, gripping her heart in the darkness.

What if he really is a strange person?

She tried calling her homeroom teacher, but the teacher didn't answer.

The voice grew closer, but the person seemed unaware of her presence, slowly ignoring her and moving to another cabinet, where they opened the door.

Xu Shuang quietly pushed open the door and immediately moved to another place.

Fortunately, the lights were off, and the corridor was pitch black, so the man didn't notice her.

She wanted to call the teacher again, but when she reached into her pocket, she realized she had left her phone in the cabinet.

This is not a place to stay for long; we must leave immediately.

Xu Shuang was about to run away when she accidentally bumped into the cabinet next to her, making a soft sound.

The footsteps stopped.

Then the voice moved quickly toward her.

"Ah!" Xu Shuang exclaimed in surprise.

"Don't be afraid, it's me."

……

Yan Qing and Bai Yi were in different interrogation rooms.

The two were in the same boat, both dissatisfied with the police's sudden arrest. However, Yan Qing kept shouting, while Bai Yi sat there impatiently.

Qin Qingzhou watched the monitor in silence for a while, then pushed open one of the doors.

He slowly sat down in the chair: "What exactly did Xu Shuang discover that made you want to kill her?"

Sitting opposite him was Bai Yi, a female teacher. Upon hearing this, she frowned and asked, "What are you talking about?"

Qin Qingzhou showed the surveillance footage to Bai Yi: "Limping, similar height, no alibi, isn't that you?"

Bai Yi almost laughed in anger: "Isn't Teacher Yan the same? Why me?"

"I didn't ask you to see this." Qin Qingzhou zoomed in on the image, focusing on Xu Shuang.

"I was certain from the moment I watched the surveillance footage that since Xu Shuang dared to walk ahead of the murderer without any scruples, the murderer must be someone she knew very well, or someone she could be completely unguarded against, such as a woman."

"And you are the one who fits this description, not only because you are her chemistry lab teacher, but also because you are a woman."

Bai Yi's throat tightened: "How can this prove I'm the murderer? Don't the other teachers and students at the school trust me?"

"He didn't finish."

Qin Qingzhou moved the surveillance camera again, this time focusing on the murderer.

"I've watched this surveillance footage many times and noticed something quite interesting."

"What?"

The interrogation room door was knocked open, and Li Ku poked his head in: "Captain Qin, the person has been brought."

Yan Qing was brought in completely bewildered.

Qin Qingzhou glanced at Bai Yi: "Get up."

Yan Qing and Bai Yi stood together, and their height and build were indeed very similar. They stood on one side of the room, both looking helpless.

Qin Qingzhou crossed her arms and looked at them calmly: "Please cooperate with me and walk to the other end of the room."

"start."

The two set off at the same time, walking slowly and sluggishly due to their limp, but there was a clear difference between them.

Li Ku's eyes widened, and he understood.

Halfway there, Bai Yi also noticed the problem, stopped and stood still, clenching his fists tightly.

"There's no need to go any further, Li Ku. Let Teacher Yan go back."

After the others left, Bai Yi stood there, his throat tight, and he had to tilt his head back slightly to swallow.

She injured her left foot, while Yan Qing injured her right foot.

"We found Xu Shuang's phone. What is that hidden room she mentioned in her messages?"

"It's nothing."

Qin Qingzhou and Bai Yi locked eyes; Bai Yi's gaze seemed to see right through her.

"Before I tell you what this room is for, I suggest you tell me first, so that you can mitigate your punishment by being honest."

"Heh..." Bai Yi suddenly laughed, and the laughter gradually grew louder and louder until he was almost in a frenzy, until tears welled up in the corners of his eyes, which he then wiped away without a care.

"Mitigation of punishment? I don't need that."

Bai Yi sat back down in her chair. In that instant, she understood what she would experience in the future, and she suddenly felt relieved.

"Don't you know what that operating room is for?"

Qin Qingzhou did not answer.

His colleagues at the scene found the hidden room and sent him photos. He knew what it was the moment he saw them.

Bai Yi raised his chin provocatively: "That was an operating room for organ trafficking. Xu Shuang discovered that operating room, so I silenced her."

"I originally planned to take her back to the operating room to use her, but I didn't expect that she was so weak that she actually jumped off the building herself."

Qin Qingzhou's fingers tightened.

Xu Shuang sacrificed her life to uncover the truth.

"But it doesn't matter anymore, I'm not going to live anyway."