Thirty-two weeks pregnant, I watched my husband walk into his family’s Christmas party with another woman wearing the diamond necklace he had secretly purchased during a hotel stay. Sixty guests were watching when I finally told him, “Since you brought someone, I brought someone too”—but Matthias had no idea that his infidelity was no longer the most dangerous secret I had uncovered.

Nathan locked the library door.

Matthias stared at Fiona.

“Your father died six years ago.”

“That’s what I was told.”

I watched her carefully.

She no longer looked like the smug woman wearing my necklace.

She looked terrified.

Fiona’s father, Gregory Vale, had been a mechanical engineer hired during the Dre estate renovation fourteen years earlier. He designed the heating and emergency shutoff systems.

Six years ago, he supposedly died in a boating accident off Rhode Island.

No body had ever been recovered.

Fiona opened her clutch.

Inside was a folded photograph.

Gregory Vale.

Alive.

The photograph had been taken two months earlier.

I stared.

“You knew?”

“I found out recently.”

“Is that why you got close to Matthias?”

Her silence answered.

Matthias looked wounded.

For one second I almost laughed at the irony.

Then Fiona said, “At first.”

Matthias turned away.

So the affair had been real.

Just built on another lie.

A hard knock hit the library door.

“Mr. Dre?”

The fake caterer.

“Dinner is waiting.”

Nathan called through the door.

“Give us five minutes.”

Silence.

Then footsteps moved away.

I looked at Matthias.

“Where is the manual gas shutoff?”

“Basement mechanical room.”

Fiona shook her head.

“If my father altered the original design, there’s a secondary control beneath the conservatory.”

Nathan said, “We don’t go looking for bombs.”

“No one said bomb.”

Fiona’s voice trembled.

“Gas is enough.”

I thought about sixty guests.

Some elderly.

Three children.

Two pregnant women, including me.

We needed panic without panic.

Matthias finally did something useful.

He called the estate security desk through the internal landline.

No answer.

Conrad’s private office line worked.

Matthias told his father there was a suspected gas problem and instructed him to move everyone to the front lawn under the excuse of a Christmas photograph.

Conrad argued.

Matthias shouted,

“Dad, do it!”

Thirty seconds later, Conrad announced a surprise family photograph outside beneath the lights.

Guests laughed and began collecting coats.

Then the fire alarm activated.

Not loudly.

Silently.

Only a red indicator flashed on the library panel.

Fiona went white.

“That’s wrong.”

“What?”