In the days after 9/11, a photo of an unknown man falling from the South Tower appeared in publications across the globe. This is the story of that photograph, and of the search to find the man pictured in it.

Why “the legal equivalent of outer space” continues to exist, fifteen years after 9/11.

How a tattooed video store clerk with a history of drinking and drug use ended up at an Islamic self-help class leading to the birth of ISIS.

A profile of Moktar Belmoktar, Al-Qaida’s “most difficult employee,” who was responsible for a major attack on an Algerian BP plant and, according to U.S. and Libyan forces, was killed in an air strike on Sunday.

The inside story of the coup that has brought the world’s most feared terrorist network to the brink of collapse.

While fleeing their Mali stronghold, al-Qaida left behind documents describing not how to terrorize a population, but how to govern.

On the American teenager who was kidnapped by Islamic militants while on vacation in the Philippines.

A history of how Tuareg separatists, jihadists seeking a “desert caliphate,” cigarette smugglers, and narcotraffickers have turned Northern Mali into “the globe’s most significant terrorist threat.”

A profile of Ayman al-Zawahri, the Egyptian doctor who became Bin Laden’s #2 and has now taken over Al-Qaeda.

A classified Guantánamo Bay interrogation log reveals the techniques used on Mohammed al-Qahtani, the so-called 20th 9/11 hijacker.

In the wake of 9/11, terrorist networks moved their recruitment and training efforts online, giving birth to Jihad-geeks like Irhabi_007.