Dr. Peyton McKean faces the greatest challenge of his life when he confronts a deadly new terror weapon: genetically altered smallpox A DEADLY MICROBE: When a U.S. Customs inspector at the Canadian border succumbs to a fatal viral infection, a terrifying fear becomes reality. Someone has smuggled a devastating genetically altered strain of smallpox virus into the country. But where is it? And just how lethal might it be? A MASTER MURDERER: Sheik Abdul-Ghazi, oil billionaire turned terrorist, has masterminded a plot to spread a plague that will kill millions. He and his ruthless henchmen are holed up on a remote western ranch, preparing to unleash their nightmare weapon on American cities. A BEAUTIFUL WOMAN: Jameela Noori, Abdul-Ghazi's Egyptian-born horse trainer, may be the consummate blend of beauty and treachery. Or is she the weak link in a diabolical scheme? THE GREATEST MIND SINCE SHERLOCK HOLMES: As the plague's first victims die, brilliant vaccine researcher Dr. Peyton McKean is enlisted by the Centers for Disease Control to track down the source of the virus and find a cure. From his lab to a horseback chase in a hail of bullets, McKean brings to bear a keen intellect and the boldness of a born adventurer. But overcoming this threat will take more than daring. It will take a medical miracle.