ISIS is a terrorist army on a savage march, but who are they, and where did they come from?

In a Fox News special, Greta Van Susteren reveals new details about ISIS leader Abu Bakr Al-Baghdadi.

Intel Bulletin Warns of ISIS Urging Jihad Attacks Against U.S. Soldiers at Home

"Greta Investigates” will show how ISIS dominates social media in a way that has surpassed al Qaeda, digging deep into the American roots of the ISIS media guru who is driving recruitment online.

In this terrorist turf war, learn how ISIS became the richest terrorist organization on earth.

5 Top Military Leaders Quoted About Defeating ISIS

Don’t miss this Fox News special tomorrow at 7p ET, re-airing Saturday at 10p ET and Sunday at 9p ET.