How does the author use foreshadowing in The Killer Inside Me?

In Chapter Ten, there is a significant aspect of foreshadowing during which Lou says he knows Chester Conway has said something important to Bob and it really "frazzled" Bob. Though Bob does not tell Lou what Chester says, Lou says he should have known. Bob also tells Lou that "it's lightest just before the dawn." Lou says Bob must have gotten the old adage wrong, but Bob says he did not get it wrong. This is also a foreshadowing, and Lou will later say that Bob was right on this count.