In Chapter 4, "Wednesday, 2:05 P.M., March 20, 1996," we hear a conversation between Chet and Jack that is designed to tell us a little more detail about Jack. As a side note, technically, this an awkward place for this information. By Chapter 7 we already have a firm image of Jack in our minds, for instance, perhaps as a tall, slim active man with brown hair parted at the left and sort of floppy, as in the British style, yet now we find out that "he is a stocky, six-foot man accustomed to serious activity." These are two very different images and men. In all probability, every reader at this point has to mentally stop, erase, and rebuild Jack's image, an exercise that detracts from the quality of the novel.
Having additional information about Jack (even though some of it would have been welcome earlier) gives us more insight into his actions and attitudes and lends cohesion to his interactions with others. After an interruption to their conversation, Chet hastily follows Jack out of their shared office into the hall after Jack has impulsively decided to take advantage in his superior's absence to get "more information" from Bart Anderson in order to pinpoint where the plague originated, a plan that worries Chet:
[Jack] got in the elevator and hit the Down button. "I need more information. Somebody has to figure out where this plague came from or this city's in for some trouble."
"Hadn't you better wait for Bingham?" Chet asked. "That look in your eye disturbs me."
In the elevator, the narrator confirms Jack's dislike of AmeriCare by reminding us of his earlier remarks through Jack's interior thoughts as he muses about his wish to "give AmeriCare some heartburn." His conversation with Bart leads to two telephone calls. One to the Commissioner of Health and one to Nodelman's wife.
Jack's conversation with Bart leads to a telephone inquiry with Mrs. Nodelman, the wife of the diabetes patient who died of the plague as the result of hospitalization for diabetes treatment. From Mrs. Nodelman, Jack learns that foreign travel, foreign visitors, a domestic pet, neighborhood rats and wild animals, like rabbits, were not the originating cause of Nodelman's plague virus.
The chapter concludes with Jack alarming Chet again by declaring it was time to apprise Laurie Montgomery of the situation that Jack had begun to sketch out:
"There's that facial expression again that scares me," Chet said. ...
"[I'm going to] tell Laurie Montgomery what's going on," Jack said. ... "She has to be apprised."