I won't lay out the plot for you, another reviewer has kindly done that in detail below. I'll just say that each of the books in the southern vampire series is better than the last. That is really saying something, because all of them are excellent.
This one pushes Bill out of the picture, and give Sookie centre stage. Sookie has gained all kinds of experience in the last three books. In book four, her skills and determination are put to the test. She is not found wanting. :)
An excellent continuation of the series. Can't wait for the next book.