 David travels to Chicago to attend the International Spanish Flu conference at which time he interviews Gill for the vacant position of head virologist at NORBAC. After spending the night with David, Gill decides not to accept the job at NORBAC. On his return to NORBAC, David and Caroline interview Harvey Thomas, a bankrupt researcher into prion type diseases like "Mad Cow". Meanwhile the team at NORBAC investigate the background of all the "Mad Cow" victims for any commonality. David and Caroline discover that the researcher went bankrupt because he had no patients on which to test his vaccine. After exhaustive checks it is discovered that all the victims ate either chicken or eggs from a particular distributor. Tests on the chicken samples show that they are all infected with "Mad Cow" prions. Tens of millions of chickens will need to be culled, however the human cost will not be known for decades. Harvey Thomas is eventually recaptured and explains why he did it and believes the government will allow him to complete his research, in fact he will be prosecuted as a bio-terrorist.