When I give these names to law enforcement, I am really sure, because all those pieces have to

come together a really specific way. And then for them to end up right in the town where these

crimes happened, it can't be a coincidence.

Do you remember the day when you figured out who it was?

Yes, I remember the moment when I finally get to all of these people.

Why?

Well, if I'm right, which I believe I am, I know a secret that only the killer knows or only the rapist knows.

It's a plan and a price tag that may have trouble ever getting out of the station.

A $40 billion, 10-year upgrade of New York City's antiquated and unreliable subway system.

Tonight, we'll go deep down to show you systems and equipment, some that have been operating since the Great Depression.

This thing was built.

Before we were born.

Long before.

Long before.

I call it all trusty.

But it's moving a dream.

In Mongolia, hunters partner with eagles in a tradition that goes back thousands of years.

One of the best at this is Lauren McGough from, of all places, Oklahoma City.

This is the most ancient form of falconry in the world.

It blows my mind that it's even real. It's like something out of Lord of the Rings, but you can do it.

We built a camera harness to learn what it's like to fly like an eagle.

I'm Steve Proft.

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