Weeks after 9-11, a second wave of terror struck the US, but this time the weapon was invisible.

Anthrax-laced letters sent the nation into panic, shutting down government buildings and overwhelming law enforcement.

The FBI launched one of the largest investigations in its history, unraveling a complex

web of scientific clues, human error, and personal cost.

The gripping new podcast series, Aftermath, Hunt for the Anthrax Killer, takes you deep inside

the case, from the science that cracked it, to the mistakes that nearly derailed it.

With exclusive access to declassified materials and first-hand accounts,

this eight-part series from Wolf Entertainment, CBC podcasts, and USG Audio,

reveals how the attacks reshaped America and the hidden consequences that still linger today.

Now stay tuned for a sneak peek of episode one.

I mean, this was a huge crime scene.

Most people don't think about it as a crime scene, but it was a crime scene of seven blocks.

The unthinkable happened today.

The World Trade Center, both towers, gone.

There are survivors trapped in that rubble mayor Giuliani.

Now it's obvious, I think. I think we have a

terrorist act of proportions that we cannot begin to imagine at this juncture. It was the evening

of September 11th, about 12 hours after the terrorist attacks, and Scott Decker, a special agent

with the FBI,

was already on the move.

He'd packed his bags and said goodbye to his family in Virginia.

I was told to grab four of the guys,

...