What is the theme in Phantoms by Dean Koontz?

Phantoms, by Dean Koontz, has a central theme that is clearly good versus evil. Though the characters in the novel have their own personal demons, they are inherently good people, caught in a terrifying situation. The first instance of good versus evil that takes place in the novel is between Bryce Hammond and Fletcher Kale. Though Kale seems to be a devastated man after the deaths of his wife and young son, it is revealed that Kale has killed his family in order to obtain the funds for an investment deal.