The threat of biotechnological warfare and/or terrorism is the focus of this carefully researched and riveting novel by the author of The Hot Zone. The term "science fiction" doesn't quite do justice to this tale which lies just to the other side of Preston's usual domain of literary nonfiction. Though the particulars of this story of a genetic engineer who designs lethal virus bombs to thin the population and the counterterrorist group of scientists who attempt to stop him are fictional, the possibilities of such threats are real.

The counterterrorists are a motley and sometimes contentious group of recruits from the FBI, the Centers for Disease Control (CDC), and the U.S. military. Their agendas and methods differ, but the immediate death threat to the unsuspecting inhabitants of New York and Washington D.C. unifies them into an effective if not always efficient team. They discover the virus when five cases appear of what seems to be an acute and horrifying permutation of a rare neurological dysfunction that induces violent seizures and compulsive self-destruction by chewing on one's own flesh. The virus turns out to be a graft that could only have been produced by artificial means.

The search for the "mad scientist" with equipment capable of this sophisticated work takes weeks during which a handful of people have to live with the secret that a potential pandemic could literally explode in a local subway. The resolution, while in some ways satisfying, hardly dispels the uneasy implications which invite readers not only to serious reflection on our collective attitudes toward weapons research and development, but to activism.