I didn't sleep that night.
Instead, I sat beside my bedroom window with the anonymous note spread across my lap.
The handwriting was uneven.
The paper had been torn from a small household notepad.
Whoever had written it knew exactly what I was investigating.
And they wanted me to stop.
At six the following morning, I found Mrs. Harper in the kitchen.
She was arranging breakfast trays.
"Good morning," I said.
She barely looked at me.
"Good morning, Miss Morgan."
I placed the note beside her.
Her hand froze above a silver teapot.
"Did you write this?"
She stared at the paper.
"No."
"Do you know who did?"
"No."
"Mrs. Harper—"
"I have worked in this house for twenty-two years."
Her voice was suddenly sharp.
"I know when to mind my own business."
She picked up the breakfast tray.
"Perhaps you should learn the same."
Then she walked away.
I watched her go.
Fear could make people cruel.
But it could also make them dangerous.
At eight, I entered the twins' bedrooms.
Lucas was sitting on his bed, struggling to button his pajama shirt.
Leo lay beneath his blankets.
"Morning, champions."
Lucas smiled.
"Claire!"
Leo lifted one hand.
"Can we play cars today?"
"Absolutely."
I helped Lucas with his buttons.
Then I checked Leo's forehead.
He wasn't feverish.
But his skin felt unusually cool.
"How did you sleep?"
"Bad," he whispered.
"Nightmares?"
He shook his head.
"My legs hurt."
Lucas looked down.
"Mine too."
I helped them get dressed.
When I opened the curtains, sunlight filled the room.
Lucas immediately smiled.
"Can we open the window?"
I hesitated.
"Does your dad usually let you?"
"Dr. Blake says outside air makes us sick."
I looked toward the ventilation grate.
The sweet chemical smell was stronger than yesterday.
"Well," I said, "let's ask your father."
Vincent was in his office when I found him.
He stood beside his desk, speaking quietly into his phone.
"I don't care how much it costs. Find someone who can inspect the entire system."
He listened.
"Today."
He ended the call.
"Good morning, Claire."
"Good morning."
"I've arranged for an independent environmental specialist to come tomorrow."
"Thank you."
He studied my face.
"Something else?"
I handed him the note.
He read it.
His expression became unreadable.
"Where did you get this?"
"Someone pushed it under my door last night."
"Did you see who?"
"No."
Vincent pressed a button on his desk.
A moment later, a tall man entered.
"Marco, review the hallway security footage between eleven and midnight."
Marco glanced at the note.
"Understood."
When he left, Vincent turned back to me.
"You're safe here."
I looked at him.
"Someone inside your house knows what I'm investigating."
His jaw tightened.
"Then I'll find out who."
"Your sons need to spend time outside today."
He frowned.
"Dr. Blake says—"
"I know what Dr. Blake says."
I stepped closer.
"But Lucas and Leo told me they sometimes feel better outdoors. I want to see whether that's true."
Vincent looked toward the family photographs on his desk.
One showed Isabella holding the twins when they were babies.
Another showed the boys playing on a beach.
They looked healthy.
Strong.
Happy.
"How long?" he asked.
"An hour. Maybe two, depending on how they feel."
He nodded.
"I'll come with you."
That afternoon, we carried the boys into the garden.
The air was cool and fresh.
Autumn leaves scattered across the lawn.
Lucas and Leo sat on a blanket beneath a large maple tree.
I brought their toy cars, coloring books, and a small basket of snacks.
Vincent sat nearby.
At first, the boys were quiet.
Then Lucas began arranging his cars along the edge of the blanket.
Leo joined him.
After twenty minutes, something changed.
Lucas's hands stopped trembling as much.
Leo sat upright without leaning against the cushions.
They began laughing.
Actually laughing.
Vincent noticed.
"Lucas?"
His son looked up.
"Yeah, Daddy?"
"How do you feel?"
"Good."
"Your legs?"
Lucas moved them.
"They still hurt a little."
Leo grinned.
"But not as much."
Vincent looked at me.
I said nothing.
We stayed outside for nearly ninety minutes.
By the time we returned to the mansion, both boys were tired but cheerful.
That evening, however, their symptoms returned.
Leo complained of dizziness.
Lucas became unusually sleepy.
I checked the ventilation grate.
The sweet odor was back.
At seven, Dr. Blake arrived.
He examined both boys and immediately questioned their afternoon outdoors.
"Vincent, this was irresponsible."
"They felt better," Vincent said.
"Temporary improvements mean nothing."
"Then explain why they deteriorated after returning to their rooms."
Dr. Blake's eyes moved toward me.
"Children with chronic illness experience fluctuations."
"Both children?" I asked.
"Yes."
"At almost exactly the same time?"
His expression hardened.
"Miss Morgan, I don't need a lesson in medicine."
"I'm not giving you one."
"Then stop interfering."
Vincent stepped between us.
"Enough."
Dr. Blake closed his medical bag.
"I strongly recommend that the boys remain in their bedrooms."
Vincent looked at his sons.
Then at me.
"No."
Dr. Blake stared at him.
"What?"
"They'll sleep downstairs tonight."
"Vincent—"
"I said no."
The doctor left without finishing his examination.
I helped Mrs. Harper prepare two guest bedrooms on the ground floor.
Neither room shared the east wing's ventilation system.
As we changed the sheets, she suddenly whispered, "You shouldn't have done that."
I turned.
"Done what?"
"Moved them."
"Why?"
She looked toward the open doorway.
"Because now he'll know."
"Who?"
Her eyes filled with tears.
Before she could answer, Marco appeared.
"Miss Morgan, Mr. Moretti wants to see you."
I followed him downstairs.
Vincent stood in the security room.
Sixteen monitors covered one wall.
Marco replayed the footage from the previous night.
At 11:41, a figure appeared in the hallway outside my bedroom.
The person wore dark clothing.
Their face was hidden beneath a hood.
They approached my door.
Bent down.
Slid the note underneath.
Then disappeared through a service entrance.
"Can you identify them?" I asked.
Marco shook his head.
"The camera covering the service hallway went offline for six minutes."
"Coincidentally?"
"No."
Vincent folded his arms.
"Someone disabled it."
Marco brought up another recording.
"This is from three nights ago."
The screen showed a man entering the east wing shortly after midnight.
He carried a black equipment case.
I leaned forward.
"Who is that?"
Vincent's expression darkened.
"Daniel Price."
"Who?"
"Our maintenance supervisor."
Marco paused the recording.
Daniel entered a locked utility room beside the twins' bedrooms.
He remained inside for twenty-three minutes.
Then he left.
"Why was he working at midnight?" I asked.
Vincent didn't answer.
Marco opened another file.
"According to the maintenance records, Mr. Price hasn't inspected that room in six months."
I looked at the screen.
"Then what was he doing inside?"
Vincent picked up his phone.
"Bring Daniel to my office."
Twenty minutes later, Marco returned alone.
"He's gone."
Vincent's face hardened.
"What do you mean, gone?"
"His apartment is empty. His phone is disconnected."
"Find him."
Marco nodded.
Then he placed something on the desk.
A small plastic access card.
"We found this in his locker."
Vincent picked it up.
The card carried the Moretti estate logo.
Underneath was a handwritten label.
EAST WING — PRIVATE MEDICAL ACCESS.
I stared at it.
"Why would your maintenance supervisor need medical access?"
Vincent turned the card over.
On the back was a second name.
DR. HARRISON BLAKE.