In the wake of the 9/11 attacks, the United States government called on prominent virology researchers, including Peter Jahrling and the seventy-three year-old D.A. Henderson. The anthrax from the letter that reached Tom Daschle was brought to USAMRIID, where Tom Geisbert determined that he was dealing with a high-quality, effectively purified sample of anthrax spores. Anthrax itself consists of cells (not simply of virus particles) and spreads by killing its hosts, seeping from their rotting bodies into the soil, and finding new hosts. Jahrling and another high-ranking official, Major General John S. Parker, are quickly alerted to Geisbert’s work. In the meantime, mail workers begin to fall ill as the direct result of passing exposure to or simply being present in the facilities that transmitted anthrax letters.

Parker reports to the U.S. Senate to discuss the severity of the threat posed by the anthrax. Jahrling, for his part, tries to explain the quality and potency of the anthrax to the CDC, but the significance of the descriptive words that he chooses (“energetic,” “professional”) is not readily apparent to his contacts. Regardless of how it is described, the anthrax was apparently created by an expert who knew the “anthrax trick” of engineering the anthrax to form clumps (or “skulls”) that would crumble in a manner meant to optimize dispersal.