In a makeshift prison in the north of Poland, Al Qaeda's engineer of mass murder faced off against his Central Intelligence Agency interrogator. It was 18 months after the 9/11 attacks, and the invasion of Iraq was giving Muslim extremists new motives for havoc. If anyone knew about the next plot, it was Khalid Shaikh Mohammed.
The interrogator, Deuce Martinez, a soft-spoken analyst who spoke no Arabic, had turned down a C.I.A. offer to be trained in waterboarding. He chose to leave the infliction of pain and panic to others, the gung-ho paramilitary types whom the more cerebral interrogators called "knuckledraggers."