Into thin air. It's a phrase you often hear when talking about people who have gone missing,

vanished into thin air, but it's usually just a euphemism. The reality is, even in the biggest of mysteries, it's nearly impossible for

someone to truly vanish without a trace. There's always one clue that ultimately holds the answers,

or at least points detectives in the right direction to look.

But, on February 9, 2004, when Mora Murray, a quiet reserve 21-year-old nursing student

from Hanson, Massachusetts, went missing, it seems that this was the exception to the rule, that she actually did just vanish into thin air without leaving behind a clue.

One moment she was there on the side of a winding road that snakes along the edge of the woods in remote, snowy,

Haverill, New Hampshire.

The next minute?

Poof.

She was gone.

It was like she had never been there at all.

Now, more than 20 years later, there are still no answers.

How is that possible in this day and time? I mean, there are so many ways that people can be found.

They leave electronic footprints with credit cards and transactions. We have drones,

cadaver dogs. We have all of these ways that people can be found living or dead. And the only

chance her loved ones have of ever finding out what really happened to her lies in figuring

out why she was on that icy road that night. What was her mindset in the days leading up to

her disappearance? And that's what I'm going to examine. You and I are going to do it together.

It's something her family, particularly her father, Fred, have tirelessly been struggling

to piece together for more than two decades. What happened that made Mara get in her car and head away from everything in her life?

And where was she going?

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