Johnny's sisters, Susan and Mary, create a chip that can be inserted into the brain to allow an individual to be connected to the internet at all times. However, that means the individual is exposed to computer threats such as viruses, pop-ups, and spyware. When The General implants the chip, which contains a virus, the virus takes over and makes him arms nuclear missiles. It is up to Johnny to defeat the virus and save the world from destruction.

Dade is fined and banned from using a computer until his 18th birthday because he hacked one of the largest databases.

The team creates a model of the virus causing an epidemic to better understand how it behaves and affects human cells. The novel virus changes continually, so it is difficult for them to create a vaccine.

A worldwide epidemic starts when humans cut down trees in an area inhabited by bats, forcing them to relocate. One bat carrying the virus dropped a piece of banana into a pig pen. One pig consumed the banana piece, and when it was slaughtered, the virus spread to the butcher's hands. The butcher did not wash his hands before he went to shake the hand of a guest, thus spreading the disease to the guest, who then spread it to other people.

War in the 21st century will be waged on many fronts -- one of which will be a digital battlefield with no guns or bombs.