What do you mean? You can't find her. Where is she? A mystery for years. Now for the first time, exclusive interviews with the investigators who solved it.

We said let's look at this thing scientifically and not focus on any specific

individual.

You're just trying to put those little pieces together to build some type of a profile of her pattern of behavior.

At what point did you get a sense she went from walking to being in a car?

Look, my daughter did not run away. I'm telling you.

Her drive to find her daughter kept everybody in the nation interested in what was going on with Brittany's case. She said he could be responsible for Britain.

That's nothing.

The responsible for anybody disappeared.

The final ping from Brittany's phone

is in an area that is swampy.

It's not an area where a 17 year old girl would be traveling. And then the FBI drops a bombshell. This is a story about a beautiful young woman who goes on spring break to Myrtle Beach and her life intersects with a monster.

She was perfectly fine and in a spot that she should have been safe.

And then she just vanishes.

There's nothing. period, cold. No one will ever hear from her again.

If you will fight all enough to spot again.

Brittany was vibrant.

Grandma got one over by reindeer.

Her smile was so beautiful, it just lit up the room.

When I had Brittany, I was 20.

That is kind of still young to have a child but it

brought a lot of joy into my life. When Brittany came into our lives it was a

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