The Guardian Orbital Defense System, a network of 104 satellites shielding the U.S. from missile attacks and establishing American hegemony in orbital space, will soon be fully operational. From its inception, mystery and controversy have surrounded the system, known as GODS. Dr. Harold Symes, the scientist who designed the system's artificial intelligence, has disappeared, leaving a calendar containing enigmatic "TM" notations. Political opponents of the system, led by Senator Leila Kahlid-Conroy, are decrying the safety of the system, asserting that its powerful weapons are operated by an artificial intelligence that could become uncontrollable and dangerous to mankind. And the system's satellites are under attack from Russian, Chinese, and Iranian hackers and antisatellite weapons. While attacks on GODS continue, FBI Special Agent Christine Lasco and other agents investigate the disappearances of Dr. Symes and retired Supreme Court Justice Warren Winton, whose personal calendar also contains the mysterious "TM" entries. Aided by Senator Kahlid-Conroy, foreign governments attempt to abduct the system's primary architect, Dr. Stanley Jacobson. Mac Slade, a former Delta Force captain, must defend Dr. Jacobson against the attempted abductions. But Slade, the fiancé of Special Agent Lasco, cannot defend GODS from the political campaign that threatens to shut it down, allowing its satellites to be destroyed by its foreign enemies. Nor can he defend the system against Project Supernova, the Chinese plan to destroy the four huge satellites that contain the Guardian system's artificial intelligence. As a Senate committee determines whether the GODS is dangerous and must be deactivated, China launches Project Supernova to destroy the system's artificially intelligent satellites. Only then are the true nature and capabilities of GODS's artificial intelligence revealed and the mystery of the "TM" calendar entries solved.