"What do you mean?"

She held up a thick piece.

"This looks like industrial safety glass."

My stomach tightened.

"Why would industrial glass be in my pool?"

She didn't answer.

Instead, she began examining the pool itself.

She checked the drains.

The filtration system.

The underwater lights.

Then she stopped at one fixture.

"This one has been replaced."

"How can you tell?"

"The housing is newer."

She removed the light.

Behind it was a metal pipe.

I stared.

"What's that?"

Dr. Mercer crouched beside it.

"I have no idea."

The pipe disappeared into the concrete wall.

It was capped.

And it looked decades older than the pool.

Officer Simmons immediately called Detective Lena Ortiz.

Within an hour, Detective Ortiz arrived.

She examined the pipe.

"Does your property have an old irrigation system?"

"Not that I know of."

"Any underground tanks?"

"No."

She looked toward Dana's house.

"Your neighbor seems to know more than you do."

Before I could answer, a loud metallic knock came from inside the pipe.

Everyone froze.

Another knock.

Then something dark began leaking around the cap.

The smell hit us almost immediately.

Chemical.

Sharp.

Oily.

Dr. Mercer stepped backward.

"Everyone away from the pool."

The crew moved.

The liquid spread through the shallow water.

It wasn't ordinary dirty water.

It was almost black.

My hands started shaking.

"Could that be toxic?"

Dr. Mercer looked at me.

"We don't know yet."

I thought of Emily.

I thought of all the times she had come out of this pool complaining that her skin burned.

I thought about Dana watching from behind her fence.

Detective Ortiz asked quietly:

"Has your daughter ever gotten sick after swimming here?"

"Yes."

"How often?"

"Several times."

She exchanged a look with Dr. Mercer.

"Then we need to treat this as a potential exposure site."

That afternoon, Emily was taken for testing.

While I sat in the hospital waiting room, Detective Ortiz called.

"We traced the pipe."

"Where does it go?"

There was a pause.

"Under your neighbor's garage."

I closed my eyes.

"What is she hiding?"

"We're trying to find out."

Then Detective Ortiz said something that made everything much worse.

"There appears to be an underground tank beneath her property."

Chapter 3 — Dana's Secret

The tank was old.

Very old.

Environmental investigators discovered it beneath the concrete floor of Dana's detached garage.