The CIA believed he was a “golden source,” a top-secret informant who had penetrated al-Qaeda and brought the agency within striking distance of the terrorist group’s senior leadership. But Humam al-Balawi, a Jordanian pediatrician turned spy, was not what he seemed. In late 2009, several months before the CIA learned of Osama bin Laden’s Pakistani hideout, Balawi appeared to offer the agency the best chance in a decade to find and kill al-Qaeda’s then-No. 2 leader, Ayman al-Zawahiri. But his stunning reports from inside the terrorists’ camp were part of an elaborate trap that culminated in the deaths of nine intelligence operatives, including seven Americans, at a CIA base in eastern Afghanistan.