This is the fourteenth book in the Anita Blake series. This book seems to be where we will work out a lot of emotional issues. In the very beginning, Anita believes she may be pregnant, and is unsure how to deal with how she is feeling about this possibility. We also see some of Richard's issues, a lot more of Anita's and even some of Asher's.
At the same time, they have a bunch of visiting Master's of the City, who have been invited to enjoy a traveling ballet group, made up entirely of vampires. And, of course, there are complications in dealing with all the visiting Masters.