Taking a break from decoding the genetic sequence of a tropical disease, Alex investigates the case of a DEA agent who died a gruesome and unexplained death on a Mob stakeout. Within hours, Alex tracks similar deaths throughout the Southwest. Is it a naturally occurring epidemic—or has a lethal bioweapon been released in the United States?

With the nation’s attention focused on a provocative presidential race, Alex’s attempts to warn Homeland Security fail. Only with the help of a rogue DEA agent and a smack-talking supercomputer will Alex stand a chance of putting an end to the devastation. As the plague spreads, public hysteria mounts. Then, while feverishly working to decode its source, Alex unwittingly exposes herself to the disease...