"Two people?" Xu Xiaodong tried to reconstruct the picture in his mind. "What would the action be?"

"Let the deceased ‘sit’ on the window sill, two people grab ahold of the window sill, and use their other hands to push the deceased from the back really hard and at the same time.” Peng Sijue guessed based on the current clues.

"That’s weird. If I said that Captain Peng and I were going to push Xu Xiaodong down now, what would we do?" Lin Dongxue asked.

"Hey, don't use me as an example." Xu Xiaodong said shyly.

Peng Sijue discussed, "I would lift his upper body while you lift his lower body and put his back on the window sill. Then, we’d lift his legs and let him fall down... This is the least labor-intensive way."

"What is the second most efficient way?" Lin Dongxue asked.

"We would carry one leg each, pick him up, and throw him out.” Peng Sijue responded.

"Like a child playing Aruba." Lin Dongxue laughed.

"Don't say that! I’m afraid of heights. I’m scared just thinking about it!” Xu Xiaodong said.

They discussed several ways of throwing people out the window. It may have been the reason for opening the window. The more Xu Xiaodong heard, the more goose bumps he felt on his body. According to the discussion, the murderers used the method that was the most taxing.

"Why would the murderers want to do this? Is there a hidden reason?" Lin Dongxue inquired.

"A ceremonial feeling!" A voice came from outside the door.

The trio turned around and saw Chen Shi standing there. Chen Shi asked, "Why don't you turn on the lights? Are you trying to scare people?” He tried to turn on the light switch, but it turned out the lights were broken.

"What did you just say?" Lin Dongxue asked.

"Xiaodong, sit on the hospital bed." Chen Shi instructed.

"Brother Chen, can you not use me as an example..."

Chen Shi ignored Xu Xiaodong’s protests and went behind him with Lin Dongxue. They each imitated the murderers and pressed a hand against Xu Xiaodong’s back. Chen Shi said, “Push together. One, two, three…”

"Aiya!" Xu Xiaodong was pushed out of the bed.

"I don't feel any sense of ritual." Lin Dongxue said.

"That's because you are someone from the outside. Think about it from the perspective of the murderers. They were very scared after they killed someone. The deceased may have been killed by one of them with a blunt object. The other can only be regarded as a witness or an accomplice. The murderer couldn’t let the companion rat them out, so they had to work together to push the deceased down.”

“Responsibility would then be balanced?” Lin Dongxue suddenly realized. “It’s like two people holding a knife at the same time, killing the victim.”

"Yes, the process of pushing the deceased down the building is like hinting that they are tied together by one rope, and no one can sell the other person out!"

"If they killed together, then their relationship must be very intimate. Siblings, friends, or husband and wife?" Lin Dongxue wondered.

"It’s a man and a woman. The fingerprints obviously belong to one man and one woman," reminded Peng Sijue.

"Go outside and check."

The four of them went outside and stood at the door of the ward. They were just out of sight of the nurse’s station at the front, and then they walked towards where the nurses could see them in their line of sight.

Chen Shi narrowed the scope down. "The murder should have occurred between the door and the end of the corridor."

Chen Shi surveyed this distance, but the ground was cleaned every morning by the cleaners. There were no traces left. He asked, "Where is Dr. Gao’s office?"

"The sixth floor, just below our location." Lin Dongxue said.

"Let’s go and have a look."

Dr. Gao’s office was next to the stairs on one side. Lin Dongxue said, “In accordance with Dr. Gao’s words, he attempted to have his way with the victim and was slapped in the face before the victim ran away.”

"What was her patrol route at night? Specifically." Chen Shi asked.

"From the fifth floor nurse station to the east, then back before she went to the west. Then she goes up the sixth floor, and heads east from the west side. From there, she’ll go to the seventh floor and then go from the east side to the west side. Finally, she’ll take the stairs back to the fifth floor.”

"Let's go to the fifth floor to have a look."

The four went down to the fifth floor and saw ward 504.

Chen Shi walked into the empty 504 ward and said, "According to the patrol route of the nurse each night, as long as the nurse passes by, she will not go through a second time."

"That is the case." Lin Dongxue confirmed.

"But the deceased passed by for a second time that night, probably because she had been harassed by the doctor. In a panic, she ran downstairs and saw what was going on in the ward."

"What was going on?"

"This ward is where Xue Chengyi’s father died at 4:00 last night!”

At the same time as Lin Dongxue's enlightenment, there was also a feeling of shivers and goosebumps. In the quiet night, the deceased ran down in a panic and saw a couple killing their loved one with a pillow in ward 504.

Chen Shi continued to speculate. "Her first reaction was to stop, and she didn’t expect to be hit on the side of her head. Maybe she died on the spot. Then, the couple wanted to dispose of the body, so they took the body to the seventh floor. From an empty ward, they opened the window and pushed her down. Then, the crime was finished.”

"It sounds about right!" Xu Xiaodong was shocked. "Brother Chen is really amazing. We thought you were slacking off. I didn't expect that you used an out-of-the-box method to solve the case."

"That’s less than flattering." Chen Shi smiled.

"Your reasoning is still missing something," Peng Sijue challenged. "Was the deceased running downstairs?"

"Ask Dr. Gao!" Chen Shi instructed.

The four men immediately went back to the bureau. Dr. Gao was sitting in the detention room feeling dejected. When he heard someone coming, he immediately rushed to the railing and said, "I am not the murderer! Let me go!"

Chen Shi handed him a meal and said, "I need to confirm one thing with you."

"I’ve said everything that needs to be said. What else is there to talk about?” Dr. Gao took the meal anyway.

"The deceased ran out of your office. Did she run downstairs or go upstairs?" Chen Shi queried.

Dr. Gao thought for some time before he said, "Downstairs!"

"Are you sure?"

“The anti-slip strips on the 5th to 6th floors are loose. There would be noise on the steps if she ran past them. I walk around every day, so I’m sure.”

Everyone exchanged a look. It seems that the truth of the matter had been revealed. Chen Shi said, "Let him go!"

Dr. Gao was very excited. "This police officer is reasonable."

Lin Dongxue scolded, "Remember to respect girls more next time."

"Of course, of course!"

After Dr. Gao left, Xu Xiaodong said, "Oh yes, Brother Chen. Captain Peng discovered new findings on the pillow, but we haven’t shown it to you.”

They went to the laboratory. When he saw the fingerprints on the pillow, Chen Shi was a little surprised. "Did two people work together? Is there such a tacit understanding?"

Lin Dongxue also expressed shock. "This is the evidence! Chen Shi, what did you find out when you attended the funeral today?"

"I feel that this couple is pretty strange. Although they were clearly detached from one another, they had an understanding between them as if they were tied up by something.”

"Was it this case?" Lin Dongxue pointed at the fingerprints on the pillow.

"I think that this state was not formed in a day or two. Yes, someone mentioned that in 2001, he struggled in starting a business. They said that something happened at that time and that God didn’t block his financial path!" Chen Shi’s eyes became cold. "Let’s check and dig up the secrets of the couple!"