Dark Seeker

I couldn't finish the book because I got so frustrated at all the times people acted inconsistently or knowledge appeared and vanished randomly to serve a plot.
POTENTIAL SPOILER:
A major villain has steadily tortured and killed members of powerful families. They have no problem finding him to order murder, but cannot find him for revenge. One family he reduced to a few members and follows the woman to finish the job. Instead of torturing her to find a book, he pauses strikes a deal to teach her son in the future. This is witnessed by an apparently upstanding man he brought along. Then he finishes murdering her.

This was one of many instances of inconsistencies in characters, motivation, and knowledge that I just couldn't go along with.