Have you ever noticed that in some books you feel like reaching out and giving the characters a really strong shake, and yelling in their ears "What do you think you're doing?" You just can't believe how stupid they are being or how they could be missing the obvious when it comes to doing what they need to do in order to survive.

Of course the problem is that they don't happen to be privy to the same information that the author has shared with you. If they don't happen to know that their opponent is a zombie and impossible to kill, they will assume a plot involving the death of that individual has a good chance of success. Unlike you, they didn't read the bit of information in an earlier chapter showing the character pulling a knife from his heart like it was a minor inconvenience.

Now there are "B" grade horror movies where the characters go down the darkened staircase into the basement where you just know that they are making the mistake that's going to cost them their lives and you can't believe how stupid they are. But that's more because of the stupid clichés of the genre than anything else.

What I'm referring to only happens in a novel when an author has managed to do accomplish two very important things; feed the reader pertinent bits of information via different characters so that we know about things like the zombie, and make us care about what happens to the characters to want to reach out and touch them. If you're in that deep it also means that the author has managed to pull you so far into the story that you're not getting out until it's over.

It will usually go without saying that if you've read the first two books in a series that the author has managed to get his hooks into you. But at the same time what is there left for him to do that will hold your interest as a reader? There are only so many plot twists that you can introduce without a story become as convoluted as an out-of-control pretzel and new characters at this stage of the game are a risk.

In his series Kingdoms Of Thorn And Bone Greg Keyes answers that conundrum with a good deal of ingenuity. In The Blood Knight, the third and most recent instalment, he begins to bring some of the earlier threads of plot together to weave into the beginnings of a picture.