When the towers fell on September 11, 2001, nowhere were the reverberations more powerfully felt than at CIA headquarters in Langley, Virginia. Almost overnight, the intelligence organization evolved into a warfighting intelligence service, constructing what was known internally as "the Program": a web of top-secret detention facilities intended to help prevent future attacks on American soil and around the world. With Black Site, former deputy director of the CIA Counterterrorist Center Philip Mudd presents a full, never-before-told story of this now-controversial program, directly addressing how far America went to pursue al-Qa'ida and prevent another catastrophe.

Heated debates about torture were later ignited in 2014 after the US Senate published a report of the Program, detailing the CIA's use of "enhanced interrogation techniques" to draw information from detainees. The report, Mudd posits, did not fully address key questions: How did the officials actually come to their decisions? What happened at the detention facilities - known as "Black Sites" - on a day-to-day basis? What did they look like? How were prisoners transported there? And how did the officers feel about what they were doing?