In the jungles of South America, a young U.S. intelligence officer has made a grisly discovery. Surrounded by monoliths covered with Runic symbols, one of America s greatest fears appears to have come true. Simultaneously in Colorado, a foreign spy is close to penetrating the mysterious secret the U.S. government has hidden beneath Denver International Airport. As Casey, Ericsson, Rhodes, and Cooper close in on their target, they will soon learn that another attack one of unimaginable proportions has already been set in motion, and the greatest threat they face may be the secrets kept by their own government.