Police arrived at midnight after the alarm was triggered.

The girl on the swing kept swinging.

The old lady pushed her from behind.

But they didn't talk. All they could hear was the swing.

The scene became strange.

"Ma'am, please stop and cooperate with the investigation."

I spoke loudly, but the old lady didn't react.

I walked over and grabbed the old lady's hand.

My colleagues stopped the swing and we saw the girl's face.

Her skin was pale and her face was twisted. She looked scared.

The girl's body was stiff and her skin was pale. It seemed she had stopped breathing.

The old lady next to her seemed strange.

She woke up and tried to break free from my grip.

"What are you doing?" Why won't you let her play on the swing?

Then she muttered to herself. "It was bright just a moment ago. How did it get dark so quickly?"

I wondered how it could have been bright just a moment ago. It was midnight now.

When she saw the little girl on the ground, she panicked and rushed over, hugging her and calling out.

"Gracie, are you asleep?"

"Gracie, wake up."

Seeing no response from the girl, she burst into tears:

"Oh god , how am I supposed to explain this to your father?"

My colleagues and I looked at each other. This person seemed to be the little girl's grandmother.

This case was too bizarre, so we took her back to the police station.

The dead girl was ten-year-old Grace Winton, the granddaughter of the elderly woman.

The forensic scientist will confirm the cause of death.

I asked the old lady to tell me what happened. She said,

"This evening, I took my granddaughter to play on the swings. We had just started for a short while when you all arrived."

At this point, she seemed very sad and shed tears.

"How could my granddaughter suddenly be gone?"

I watched her quietly; she didn’t seem to be lying.

But the short while she mentioned was actually nearly six hours.

I thought the old lady in front of me might be mentally ill.

I asked her to confirm.

"Your granddaughter has been on the swing for almost six hours."

She looked astonished.

"What do you mean? We only played for half an hour."

I thought the woman might have dementia.

She forgot what time it was and kept taking her granddaughter to the swing.

The girl realised something was wrong and wanted her grandmother to stop, but the grandmother didn't react. The girl was scared on the swing.

The man who reported the case said he went downstairs after dinner at six and saw the elderly woman and the girl swinging. The girl was laughing, so she was still alive.

When he came back at seven, they were still playing and he didn't think much of it.

He saw them still swinging at midnight when he went downstairs to buy cigarettes.

It was late at night and quiet.

The area was sparsely populated.

The scene became terrifying and he lost control.

He was so frightened that he quickly went home and reported the incident.

At this time, Grace Winton's father, James Winton, also arrived at the police station.

He looked like a middle-aged man, with red eyes, as if he had already cried.

He opened his mouth, dazed.

"Officer, this is an accident. My mother won't be in trouble, will she?"

He took out a mental health certificate.

The certificate showed that Grace Winton's grandmother had dementia.

This was probably an accident.

The only thing the old woman had to face was her granddaughter's death.

James Winton said his daughter had a heart disease and couldn't handle too much.

I asked: "Why didn't you look for your mother and daughter when they didn't come back?"

He looked away and said, "I was drinking with friends; I'm to blame for being greedy for alcohol."

The report came out the next day.

The report said Grace Winton died of a heart attack from shock.

This was my theory: an accident.

I sighed and said,

"What a tragedy for the family."

Forensic forensic scientist Adrian Wu disagreed. He said:

"It's not certain if it's heartbreaking."

I asked him what he meant. He sighed and continued.

＂The girl was malnourished. She was pale, thin and had dry hair. If they loved her, why was she malnourished?＂

Adrian Wu took a sip of water and continued.

"My tests show the girl died between 5 and 7 yesterday afternoon. You said the informer first saw them around 6 pm. But between five and six o'clock, their whereabouts are unclear."

"You mean the girl might have died between 5 and 6, and the swing wasn't the first crime scene?"

Adrian Wu nodded.

But I quickly dismissed Adrian Wu's view.

I apologised by patting him on the shoulder.

"Your analysis is right, but I forgot to tell you one thing. The informant said at 6 pm that he heard the girl laughing, so she was still alive when she got on the swing.

Adrian Wu laughed helplessly.

"I overthought it."

The case was strange. The girl was scared to death on a swing.

If we don’t handle it flawlessly, it might be hard to convince everyone.

I went back to the scene and spoke to nearby residents.

This is an old apartment building for the elderly.

It's a stairwell with few people coming and going.

I went up to the door and knocked.

An old man opened the door. He lived with his grandson.

I asked,

"Excuse me, sir.　Did you see anyone on the swing on 7 September between 5 pm and 7pm?"

The old man shook his head. He hadn't seen anyone.

I was disappointed and was about to leave.

But his grandson suddenly came over and shouted at me.

"Sir, why don't you ask me? I saw it and recorded a video."

I turned around and asked him to show me.

The video was shot at 6:02 pm and was only 30 seconds long.

It showed Grace Winton and her grandmother.

The two were having a good time and you could hear Grace Winton laughing.

This was sufficient proof that Grace Winton's death on the swing was an accident.

I copied the video and watched it again at the police station.

The swing was moving too fast in the video, and Grace Winton's face was blurry.

I gave the video to my colleague to fix.

The result was terrifying.

The video was restored, and Grace Winton's face was clearer but also more terrifying.

Like when we found her that night.

Her mouth was open, her eyes bulging, her face twisted, and her complexion pale.

She was dead.

The video kept playing and Grace Winton's corpse on the swing seemed to laugh, leaving everyone with fear.

Why would a dead person laugh?

Something's wrong, but I don't know what it was.

I went outside for some fresh air.

A kindergarten was next to it, with lots of children swinging.

Laughter and screams filled the air.

This reminded me of Grace Winton, so I watched for a while.

I suddenly knew where the problem was.

The video had the wrong laughter.

The children at the kindergarten only laughed or screamed when the teacher pushed them up, not when the swing came back down.

In the video, Grace Winton screamed when the swing came back down.

The sound in the video was fake.

Grace Winton's grandmother was lying!

I retrieved her grandmother’s phone, an old smartphone model from ten years ago, which was extremely sluggish and took forever to respond.

In her phone, there were several videos of Grace Winton swinging.

I copied them and asked the technicians to compare their audio with the 30-second video we obtained.

Sure enough, the audio from that 30-second video originated from one of the grandmother’s videos.

She was playing a video of her granddaughter swinging loudly on her phone while pushing the swing.

People passing by thought Grace Winton was still alive because they heard laughter.

It was dark and the swing was moving, so it was hard to see the person's face.

After the witnesses passed, she turned off the video.

The witnesses thought the girl was still alive, which misled the police.

If we hadn't got the video, she would have got away with it.

The old lady looked clumsy, but her thoughts were precise.

She didn't seem demented.

Why would she do this?

If she killed her, there was no need to move her granddaughter to the swing.

I realised she was probably trying to hide the crime scene.

Grace Winton's death might not have been an accident.

Her grandmother, Lana Winton, was likely covering for someone.

Who would make an old lady take the blame for murder?

Her son, James Winton.

I questioned Lana Winton again in the interrogation room.

I put the video in front of her and said,

"If you didn't kill your granddaughter, why are you lying?"

She looked uneasy and trembled.

I warned her firmly.

"Helping someone avoid blame is also a crime. "＂Confess now and don't get involved!"

She cried and couldn't speak. Her mind was on the verge of breaking.

I asked her:

"Whose crime are you covering for?"

She was upset and cried for a while, but she stayed silent.

Once she calmed down, she resumed a cold demeanor:

"I killed my granddaughter. I'm not taking the blame for anyone."

I was angry and slammed my hand on the table.

The case has changed and the focus is on James Winton.

Lana Winton refused to speak, so we had to find out more.

At this time, other colleagues made new discoveries.

At 5:20 p.m., James Winton's account was transferred one hundred thousand dollars.

Grace Winton died between 5:00 and 6:00 p.m. that day, making that transfer suspicious.

My colleagues and I went to James Winton's house.

This was probably the first crime scene.

He looked nervous when he saw me.

He wiped his hands on his clothes and shook my hand.

"Why are you here, officer?"

"When will my mother be released?" "She shouldn't go to jail, right?"

This man was not as honest as he appeared, and I did not offer him any pleasantries.

His right hand froze and pulled back.

“You should worry about yourself first”, I said sternly.

"Where were you between 5 and 6 pm on the night of the incident?"

He answered quickly.

"I was at home."

Then he looked surprised.

"You don't think I killed my daughter, do you?"

He brought it up himself, cutting right to the point.

I ignored his question and kept asking him:

"Who can testify for you?"

He said,

"My wife and mother can testify for me. At the time, my wife and I were chatting at home.＂

"This is impossible." "How could I have killed my own child?"

"Even beasts don't eat their young; do I look like the sort of monster who would do that?"

Remembering the forensic's report about Grace Winton's chronic malnutrition, I thought he indeed was as bad as one could be.

But my professional discipline held me back from saying anything rash, forcing me to curse only inwardly.

James Winton said his wife was working elsewhere when the police contacted the family after the incident.

But now he says his wife was at home on the day of the incident.

Does he even know where his wife is?

Or is he hiding something?

He explained.

"My wife said she was going to work after seeing me."

I asked again:

"What did you talk about?"

James Winton's eyes rolled.

"We talked about the child's studies. It's rare for her mother to come back."

If he cared about his daughter's studies, he wouldn't have let her starve.

He wouldn't speak honestly without evidence.

His eyes were cunning. I stared at them and said,

"What about that one hundred thousand dollars transfer?"

His face paled and he sweated.

His voice trembled:

"My wife and I are getting a divorce. She gave our daughter one hundred thousand dollars in child support."

He said he and his wife were getting a divorce and she didn't want to raise the child.

I asked him again:

"Why doesn't she want to raise her?"

He seemed angry.

"What else could it be?" "That bitch is cheating on me."

These are just his words and need checking.

I took a tour around his house, an old two-bedroom apartment.

James Winton's room was inside, and Lana Winton's was outside.

I asked James Winton where his daughter lived.

He stammered, "She lives with her grandmother."

I didn't see any of Grace Winton's things in her grandmother's room.

I told James Winton with a frown:

"Who does she live with?"

James Winton's eyes avoided mine. He pointed to a corner of the room and then lowered his head. I saw a folding bed and a small table. On the table was a neat stack of textbooks. There was a hook on the wall, hanging a small, worn-out schoolbag. It seemed to contain quite a few books.

I took it down and opened it.

The schoolbag was filled with ripe mangoes.

Grace Winton didn't have her own room; this was it.

A drawer on the small table held a delicate notebook.

This was Grace Winton's most precious thing.

I opened a page and found Grace Winton's diary.

6 September.

My desk mate, Ethan Jordan, is so annoying!

Today he brought a huge mango, as big as half my face.

He said his aunt bought it for him, cost 20 dollars per kilogram.

He took a bite and said it was bad, ready to throw it away.

I hadn't eaten a mango since I was a child.

I took it and said I'd help him.

I took a bite and it was soft.

Mangoes taste sweet and fragrant.

I threw it away after two bites.

I told Ethan Jordan it was bad.

After he left, I ate the mango again.

He saw me and laughed, "Grace Winton, have you never eaten a mango?"

The whole class laughed.

Everyone started mocking me.

I blushed and argued loudly. "Of course I've eaten mango before!"

They didn't believe me.

I told them. "I'll bring one tomorrow!"

My mum is coming to visit tomorrow and I'll ask her to buy me a mango.