Ouyang Ping and his entourage first went to No. 206 of Building 5 - Mr. Ma's house.

Director Feng went with him.

A lamp was installed in the corridor of Unit 2 of Building 5, and in everyone's impression, the corridor of Unit 2 was originally without lights.

Teacher Ma's house really has a doorbell.

Chen Jie also conducted a test on the spot, he asked Zuo Xiangdong and Li Wenhua to climb to the third and fourth floors respectively, and rang the doorbell twice, the result was that Zuo Xiangdong and Li Wenhua both heard the doorbell, according to which it can be inferred that the old couple of the Hao family should be able to hear the doorbell, even if there is the sound of rain, the old couple should be able to hear it.

This judgment was quickly proven, and when Chen Jie rang the doorbell for the second time, the door of No. 205 opened.

The man who opened the door was a man about forty years old, who looked at the comrades standing at the door of Teacher Ma's house with a melancholy face, but did not say anything.

After a while, a woman in her thirties came out of the room, holding a little boy of seven or eight years old, who was holding the woman's thigh tightly.

Ouyang Ping temporarily decided to start the investigation with No. 205: "May I ask your surname?" ”

"Don't have your surname Men - my name is Men Qiusheng."

"Did you hear the doorbell of Mr. Ma's house?"

"Yes, we heard the doorbell, and the first time it rang, we heard it."

"Can we talk to you?"

"Yes." The sound of the door turned on the electric light in the living room, which had been blinded by the black light before.

In Chen Jie's impression, on the evening of the 12th, in the neighborhood committee, he did not see Men Qiusheng and his wife, the couple seemed to work in a woolen factory, and on the evening of the 12th, they worked a small night shift (the small night shift was from 3:30 p.m. to 11:30 p.m. in the night).

At that time, there were too many clues, and everyone was busy, so these two people were ignored.

Everyone was just about to walk into Menqiusheng's house, and the door of No. 204 also opened, and it was Aunt Hao who opened the door.

Ouyang Ping and Han Lingling walked over.

"Auntie, did you hear the doorbell of Mr. Ma's house just now?"

"I heard it, I heard it twice, since the accident at Mr. Ma's house, at night, we closed the door early and went to bed early."

"Auntie, why is that?"

"It's not quiet in my heart, although it happened at Mr. Ma's house, it made the hearts of people on our floor stunned. You see, every family hangs a strip of red cloth on the door (according to tradition, if one of the neighbors dies, they tie a strip of red cloth to the door of the neighbor's house to ward off evil spirits). On the third floor, the Gao family has sent their two grandchildren to live with their grandmother. The Xu family on the fourth floor originally wanted to sell the house, but as soon as they heard about Mr. Ma's family, they didn't buy it. ”

Since Mr. Ma's house is a murderous house, the neighbors on the left and right will naturally be contaminated with some bad luck.

"Auntie, yesterday afternoon, did you and Uncle Ma hear the doorbell of Teacher Ma's house?"

"Hear me, old man, come out for a moment."

After a while, Uncle Hao walked up to Aunt Hao's side.

"Old man, did we hear the doorbell of Mr. Ma's house yesterday afternoon?"

"I heard it, the doorbell of Mr. Ma's house rang twice."

"What time is it?"

"A little after four! We were watching TV in our room. ”

The doorbell should have been rang by the murderer.