The "boomerang box," a high-tech computer program designed to save a plane experiencing flight trouble, is Dr. Ben Cole's baby. After a test run over the Gulf of Alaska goes awry, he suspects someone has sabotaged the plane's computer systems. And mysteriously, and almost simultaneously, April Rosen is horrified to learn that her father's plane has narrowly escaped a mid-air collision over the same patch of sea.

While Dr. Cole considers the uncomfortable notion that someone within his own company might wish him harm, Rosen begins her search for the cause of her father's hair-raising "near miss." But what both don't know is this: their fears have a common source. They are being watched by people in the Pentagon, who believe that the two might stumble upon the secret that will destroy them all before Skyhook has a chance to succeed.

What is Skyhook's real purpose? Is it commercial or military? And will its early implementation compromise the safety of flyers everywhere?