The CEO of a billion-dollar software conglomerate is killed when the company's private jet crashes in Colorado. Two National Transportation Safety Board investigators, Go-team leader Mike O'Hara and computer engineer Sally Montez, take on the case. Mike is an ex-Naval officer, ex-astronaut and serial ex-boyfriend, and Sally is a top computer expert who has two fighter-pilot ex-husbands. They discover that hackers may have inserted bogus software into the plane's flight control computers. An FBI agent assigned to the case reveals a tangle of intrigue involving an attempted hostile takeover of the corporation, which is worth billions. The Bureau zeros in on a disgruntled conglomerate vice president as the prime suspect. He crumbles under the pressure of questioning but denies guilt. As the investigators and FBI close in on the source of the hacking, Mike and a colleague are involved in separate, one-car crashes that can't be explained. Mike suffers a concussion and the other man is left in a coma. Then another corporate plane disappears off the radar screens over the Atlantic, this one carrying an engineer with facts that will solve the mystery of the original crash. Again, all on board the plane are killed. Mike and Sally push on with the investigation, ferreting out crucial facts and technical clues that put the entire case in doubt. Although the hacks and crashes put them in danger, the two investigators identify and smoke out the murderer, relying on their skills, imagination and nerve.