December 29th, 1975, LaGuardia Airport.

The holiday rush, parents hauling luggage, kids gripping their new Christmas toys.

Then, at 6.33 p.m., everything changed.

A bomb went off with such force that it ripped apart the ground-level locker room. 3.3 p.m., everything changed.

A bomb went off with such force that it ripped apart the ground-level locker room and baggage area of the main terminal.

11 people lost their lives and 75 others were injured.

The injured were being loaded into ambulances, just a chaotic, chaotic scene.

In its wake, a new kind of enemy emerged, and it was here to stay.

Terrorism.

Law and order, criminal justice system is back.

In season two, we're turning our focus to a threat that hides in plain sight.

That's harder to predict and even harder to stop.

That was not just a small bomb. It turned out to be 22 sticks of dynamite.

They left one fingerprint and there are 130 bombings.

We're exploring some of the most destructive acts of terror in America's modern age.

It created a crate of half the size of a football field.

It registered 3.2 on the Richter scale, like an earthquake. It was a tremendous roar.

And how it shaped the playbook we still use today. She put together that drawing of Timothy McVeigh

within an hour. We've got McVeigh identified. From investigators on the front lines,

One of the guys jumps up on the hood of the armored car and opens fire into the windows.

I then returned fire with my shotgun. To everyday people whose lives changed in an instant.

That's when the bomb went off. It was just this extremely loud, roaring in my head.

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