Good versus Evil

The "good guys" are constantly battling the "bad guys" throughout this story. The most obvious case is when Margo, D'Agosta, Pendergast, Mephisto, and the Navy SEALS actually fight the creatures, but there are other instances as well. One of those occurs before the story starts as Greg Kawakita realizes that he's started something that he can't take back, and looks for a way to battle the evil situation, even though that situation is of his own making. While Greg obviously had some level of "good" still in him, he sought help from a person who was not able to fight that evil when he asked Dr. Frock for assistance.

There were other instances of the good versus evil theme taking place above ground. Though not as overtly "evil," the police officer named Waxie is representative of all that is evil in a person - laziness, sloppy...