This is a tragedy on top of a tragedy now.

It happened so quickly, their parents in the backyard spa, their mom in trouble.

My dad just hit it.

A sudden slip, a fatal fall, you're losing your mother.

Watching her go right in front of you.

Someone else was watching her too, a curious neighbor just moments before witnessed something

astonishing.

It was scary. The look on his face was almost undesirable.

What had she seen was this drowning really an accident.

She's got a huge cash on her head.

Something like that is an icon system that was just falling down.

A husband and father is suddenly under suspicion.

He's crying, we're crying.

He said that you think I hurt mom.

Three daughters stand by their dad and one prosecutor stands firm.

He's holding his wife for almost three decades under the water.

My job is to get justice for Christie Hall.

Was it murder?

Someone was watching.

Good evening and welcome to Deadline.

I'm Lester Holt.

Tonight, a story that calls to mind the master of suspense.

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