"They came out of nowhere." That was the common refrain when ISIS captured the world's attention by seizing large swaths of Iraq, declaring an Islamic caliphate, and initiating a series of deadly terrorist attacks around the globe, including in Paris and Brussels. But as FRONTLINE reveals in grim detail, the emergence of the brutal terrorist group should not have been a surprise--especially to the U.S. government. 

The Secret History of ISIS investigates the inside political story of how the American invasion of Iraq and the decisions of two Presidents helped to lay the groundwork for ISIS to grow into the world's most feared terrorist group. Going behind the headlines, the film shows how Abu Musab al-Zarqawi, a one-time thug turned jihadi leader, was able to outmaneuver the American government for a time and build a brutal terrorist organization that would destabilize the Middle East and inflict violence around the world. 

The film draws on a rich archive of footage, documents, and more than 20 revelatory interviews with key policymakers including former Secretary of State Colin Powell, former Secretary of Defense Chuck Hegel, and former U.S. Ambassador to Syria Robert Ford; CIA insiders, and numerous journalists and counterterrorism experts. From veteran FRONTLINE filmmaker Michael Kirk and his acclaimed investigative team, The Secret History of ISIS is essential viewing for anyone who wants to understand how ISIS came to be, and how we got here.