“Angel is next.”The coded message crackled through secure channels, freezing everyone aboard the massive aircraft. Only a handful of people were cleared to know this classified call sign—yet here it was, transmitted on a frequency reserved for the highest levels of military communication.Colonel Mark Tillman’s eyes darted to his radar display. An unidentified aircraft had gone dark—transponder silent, no radio contact—and was flying uncomfortably close to their flight path.Tillman banked the enormous jet sharply, executing evasive maneuvers rarely used outside of training scenarios. His passengers included the most powerful person in the world, now potentially in the crosshairs of an unknown threat.In the conference room six rows behind the cockpit, Secret Service agents whispered urgently as military commanders demanded fighter support. Through the cabin windows, the peaceful blue sky suddenly seemed dangerously exposed.What had begun as a routine flight had transformed into something unprecedented: Air Force One—the flying fortress that had never been successfully attacked in its history—was now being hunted.