I'm Lester Holt. Tonight on Dadeline, a double mystery, could solving one untangle the other.

There were questions, really strange things about her disappearance.

Something just wasn't right. We just have no idea what happened at Pam.

New twists and turns in a heartbreaking story.

When you watch the video, framed by frame, you start to see little things that don't make sense.

A couple of text messages came in that we need to look at the brother Derek.

It's awkward to have to ask somebody, did you kill your sister?

She told me that she met Jose. I knew that this was pretty serious.

On a first take, how does Jose come across?

Works hard, serve this country.

You knew something bad had happened. I wanted to find Pam.

When they were on the scene, someone remembered that six-mile south from there, they had found some other remains.

His first wife, Marta, who's disappeared off the face of the earth.

We have wife number one missing and now Pam Butler missing.

He was named as a beneficiary in her will. Is there possible mode of there?

Some pulses take longer than others.

Pam's cell phone pinged, so is Pam alive? Or is this the day we find her body?

Here's Dennis Murphy with a haunting stretch of road.

These grainy nighttime images are some of the last known moments in the life of a successful woman, a person who simply vanished without a trace from her home.

What happened inside that house?

You might know some of her story, but solving what happened to her opened up an entirely new saga you don't know about another missing woman.

It's a big puzzle.

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