A research team at Dyodyne Labs has developed a remarkable new technology: a microscopic computer system with the ability to secretly track people with pinpoint accuracy. The system, code-named DaNA, is transmitted as a benign virus that passes the tracking system to all who come in contact with its host. The government sees the system as the perfect way to track down a criminal's accomplices, making it invaluable in bringing down the drug cartel. But when the biggest terrorist attack in U.S. history devastates New York City, the Department of Homeland Security orders the team to launch the untested system to find those responsible. What they uncover is unthinkable-six nuclear bombs hidden in six major cities. And the bombs, controlled by a powerful underground alliance, are part of a much larger global conspiracy. As the team at Dyodyne rushes to track down the terrorists holding the country hostage, they discover yet another threat: DaNA is mutating and may be impossible to control.