Evil

The theme of Evil is deeply explored in Blood Work. Crimmins is supposed to be the living representation of Evil in the book .

Crimmins has well played his plan. He has trapped McCaleb. McCaleb is forced to work on Gloria's case thanks to Crimmins' cleverness. His well thought plan leads McCaleb to say : "I am alive because she is dead and that cuts me into this a big way." (p187) When you know how McCaleb was played, you can't help but think he ought to have say : Crimmins cuts me into this a big way...
I think the main sign of recognition of Evil is cleverness. Of course, it is not any kind of cleverness, it is the one used to hurt, but mainly, to be Evil, you have to be clever enough to trap someone so that they can do nothing but obey you. Basically, McCaleb is not far away from being a puppet manipulated by Crimmins. He does everything as Crimmins expects him to do. Well, everything but the end, since Crimmins did not expect McCaleb would kill him.