The moment Do-hyun stepped into the Hwang Mansion, he knew something was different.
The house was quiet.
Too quiet.
Yerin was sitting in the living room, her phone resting on the table beside her. She looked up the second she heard the door open.
Do-hyun walked inside.
Their eyes met.
Yerin immediately noticed his expression.
She stood.
"What's wrong?"
Do-hyun took off his coat.
"Where's everyone?"
"Most of the staff are in the kitchen. Why?"
He didn't answer immediately.
That was enough to make her nervous.
Yerin walked closer.
"Do-hyun."
He looked at her.
"We need to talk."
Her expression changed.
"About Grandmother?"
He nodded.
Yerin's heart sank.
"Did you find something?"
"Yes."
She waited.
Do-hyun reached into his coat and took out his phone.
He opened the security report.
"I got the complete records."
Yerin stepped closer.
"What records?"
"The restricted entrance."
She stared at him.
He turned the phone toward her.
"There was an entry that night."
Yerin's eyes moved across the screen.
11:47 p.m.
Someone had entered the mansion.
She looked at Do-hyun.
"Who?"
"That's what we're trying to figure out."
"Was it a servant?"
"No."
"A guard?"
"No."
"Then who?"
Do-hyun's expression hardened.
"They used an authorized family access code."
Yerin went completely still.
"What?"
"The system recognized the code as belonging to someone from the Hwang family."
Her eyes narrowed.
"That's impossible."
"I thought the same."
"Who has access?"
"Your father. Ji-hoon. Your mother. Senior security personnel. A few people who have been trusted with emergency access."
Yerin shook her head.
"None of them would do this."
"I know."
"Then there has to be a mistake."
"We're checking everything."
She stared at the phone again.
"Show me."
Do-hyun handed it to her.
Yerin read through the report.
Entry time.
Exit time.
Access point.
Authorization.
Everything was there.
Her fingers tightened around the phone.
"Someone was inside."
"Yes."
"While Grandmother was here."
"Yes."
Her voice became quieter.
"And we didn't know."
Do-hyun didn't answer.
Yerin looked up.
"Why didn't the alarm go off?"
"Because the code was authorized."
"Security cameras?"
"One of them was disabled."
Her eyes widened.
"For how long?"
"Seven minutes."
Yerin slowly lowered the phone.
"Seven minutes..."
"Enough time for someone to enter, reach a specific area, and leave."
She looked toward the hallway.
"Someone knew exactly what they were doing."
Do-hyun nodded.
"That's what worries me."
They moved to the study.
Do-hyun placed the security files across the desk.
Yerin stood beside him.
She looked through the records one by one.
"Food deliveries."
She picked up another page.
"Nothing unusual."
Do-hyun nodded.
"Keep going."
"Medicine?"
"Already checked."
She looked at the list.
"Grandmother's medication was delivered by the regular supplier."
"Correct."
"Visitors?"
"Three that day."
"Who?"
"Two business guests and one family acquaintance."
Yerin looked at him.
"Names?"
He gave them to her.
She stared at the list.
"I don't recognize one of them."
"Neither did I."
Yerin looked up.
"Who was he?"
"He claimed he was delivering documents."
"Did security confirm it?"
"They checked his identification."
"Then why isn't there a proper record?"
Do-hyun paused.
"Exactly."
Yerin stared at him.
For the first time, the pieces seemed to be forming a pattern.
Someone had entered.
A camera had been disabled.
A visitor had appeared without a complete record.
And Grandmother had become critically ill soon afterward.
Yerin stepped back.
"Do-hyun."
"Hm?"
"What if someone inside helped them?"
He looked at her.
"That's possible."
"Then we need to question everyone."
"We will."
"Today."
"No."
She frowned.
"No?"
"We can't."
"Why?"
"Because whoever did this might realize we're investigating."
Yerin's jaw tightened.
"And then?"
"They'll know what evidence we have."
She understood.
If they moved too quickly, they could lose the person responsible.
Yerin took a slow breath.
"Fine."
She looked at the documents.
"We do this quietly."
"Exactly."
Yerin's phone suddenly rang.
She looked at the screen.
Ji-hoon.
She immediately answered.
"Oppa."
"Yerin."
His voice sounded unusually serious.
"Are you okay?"
"Yes."
There was a pause.
Then Ji-hoon asked,
"Did Do-hyun tell you?"
Yerin looked at Do-hyun.
"About the security records?"
"Yes."
"How did you know?"
Ji-hoon didn't answer.
Yerin's expression changed.
"Oppa."
"I had a feeling you'd find it eventually."
"Find what?"
"Someone accessed the mansion."
Yerin stood straighter.
"You already knew?"
"I suspected."
"Then why didn't you tell me?"
"Because I didn't have proof."
Yerin looked at Do-hyun.
"Do you know whose code was used?"
Ji-hoon became silent.
"Oppa?"
Finally, he spoke.
"Not yet."
Yerin frowned.
"You're lying."
Do-hyun looked at her.
She had already recognized that tone.
Ji-hoon sighed.
"There is one person whose code should never have been active that night."
Yerin's heart started beating faster.
"Who?"
"I need you to promise me something first."
"What?"
"Don't confront anyone."
"Why?"
"Because if I'm right, confronting them could make everything worse."
Yerin tightened her grip on the phone.
"Tell me who it is."
Before Ji-hoon could answer—
The call disconnected.
Yerin stared at the screen.
"Oppa?"
Nothing.
She called again.
No answer.
Do-hyun walked toward her.
"What happened?"
Yerin slowly lowered the phone.
"He knows something."
"I figured."
"He wouldn't tell me."
"Then we'll find it ourselves."
She looked at him.
"Do-hyun..."
"Hm?"
"What if it's someone close to us?"
He looked at her for a moment.
"Then we'll find out."
Later that afternoon, Do-hyun returned to his office.
His assistant was waiting.
"You asked for the complete access history."
"Yes."
The assistant placed a file on the desk.
"We found something."
Do-hyun opened it.
"There's another entry."
He looked up.
"When?"
"Three months before Grandmother became ill."
Do-hyun's eyes narrowed.
"Same entrance?"
"Yes."
"Same code?"
The assistant nodded.
"The exact same code."
Do-hyun stared at the report.
Three months earlier.
Someone had entered the mansion using the same authorization.
He turned the page.
"Was the camera disabled then?"
"Yes."
His expression changed.
"How long?"
"Six minutes."
Do-hyun slowly leaned back.
"Six minutes..."
The assistant nodded.
"And there's something else."
"What?"
"The person didn't enter randomly."
He placed another document on the desk.
"Their movement was tracked through the available cameras."
Do-hyun studied the map.
The person had gone through the restricted hallway.
Then toward the old family records room.
His eyes stopped.
"The records room?"
"Yes."
"What did they take?"
"We don't know."
"Why?"
"Because the camera inside that hallway was also offline."
Do-hyun stared at the screen.
Three months before Grandmother's death, someone had entered the mansion.
They had used the same family access code.
They had disabled the same cameras.
And they had gone directly toward the family records.
This wasn't random.
It had been planned.
Yerin was sitting alone in Grandmother's old room.
The room had barely changed.
Her books were still arranged on the shelf.
Her favorite chair was still beside the window.
Yerin walked toward it.
She gently touched the back of the chair.
"Grandma..."
Her voice was barely above a whisper.
She sat down.
For a moment, she closed her eyes.
She remembered Grandmother's voice.
Her advice.
Her smile.
Everything.
Then she opened her eyes.
Her sadness slowly turned into determination.
"Whoever did this..."
She looked toward the photograph on the table.
"I'm going to find you."
Her phone vibrated.
A message from Do-hyun.
Come to the study. Now.
Yerin immediately stood.
Something in the message told her this wasn't normal.
She walked quickly toward the study.
When she entered, Do-hyun was standing beside the desk.
He looked at her.
"I found something."
"What?"
He turned the laptop toward her.
Yerin stepped closer.
A security report was open on the screen.
Her eyes moved down the page.
Then stopped.
The same access code.
Three months earlier.
Same entrance.
Same disabled camera.
Same pattern.
She slowly looked at Do-hyun.
"This happened before."
He nodded.
"Yes."
"Why?"
"We don't know."
She stared at the report.
"Where did they go?"
Do-hyun pointed to the map.
"The family records room."
Yerin's face changed.
"The old records?"
"Yes."
"Do we know what they took?"
"No."
She was silent.
Then she whispered,
"So they weren't after Grandmother."
Do-hyun looked at her.
"Maybe not."
Yerin looked back at the screen.
"Then what were they looking for?"
Neither of them had an answer.
But one thing was becoming clear.
Grandmother's poisoning wasn't the beginning.
It was only the moment they finally noticed someone had been moving in the shadows for much longer.
Do-hyun opened another file.
"This is the final access report."
Yerin looked at him.
"You found the name?"
He nodded.
She stepped closer.
"Show me."
Do-hyun hesitated.
For the first time since she had known him, Yerin saw genuine uncertainty in his eyes.
"Do-hyun?"
He turned the laptop toward her.
Yerin looked down.
The name appeared on the screen.
Her expression changed instantly.
She didn't speak.
She simply stared.
"No..."
Do-hyun watched her carefully.
Yerin shook her head.
"That's not possible."
"Yerin..."
"No."
She took a step back.
"There's no way."
Her eyes remained fixed on the name.
It belonged to someone she had trusted for years.
Someone who had always been considered part of the family.
Someone whose presence in the mansion had never raised a single question.
Yerin's voice became barely audible.
"Why would they..."
She couldn't finish.
Do-hyun stepped closer but didn't touch her.
"We don't know if they actually used the code."
Yerin looked at him.
"But the system says they did."
"Yes."
"Then why?"
"I don't know."
She looked back at the screen.
The room became completely silent.
The name remained there.
Impossible.
Unbelievable.
Yet undeniable.
Yerin slowly closed her eyes.
For years, she had believed that the people closest to her were the people she could trust the most.
Now she wasn't sure anymore.
Do-hyun looked at the report once again.
There was still one question neither of them could answer.
If that person had used the access code months before Grandmother's poisoning...
what had they been looking for?
And more importantly—
what had they found?
...To Be Continued...