For 19 days, a bomber held Austin, Texas, hostage — residents of the city paralyzed by the fear of unpredictable strikes.

By the time authorities caught up with the suspect, six bombs had detonated, two people were dead and five were injured.

A year has passed, but for the first time, ABC News' “Nightline” takes you inside the investigation that brought down one of the most prolific bombers in American history, through the eyes of law enforcement on the ground — the Austin police, the bomb squads, FBI and ATF agents – and by revealing never-before-seen details on how they found him.

“In the history of this country, we haven't had a serial bomber that planted this many devices in a 19-day period,” said Fred Milanowski, the ATF special agent in charge of the Austin probe.

Read more: ABC News