Incarceron, Finn is now living in the Outside with Claudia, but he's not satisfied being the heir to the throne. His oath brother, Keiro, is still in Incarceron, as is the former dog slave, Attia. As fights for power occur both in and outside of Incarceron, the novel follows each character as he or she chooses loyalties.
Musings: I enjoyed Incarceron, despite its somewhat convoluted (and pretty forgettable) plot, and I feel the same way about Sapphique. When I first began listening to it, I had to look up a detailed summary of the first book because I remembered nearly nothing about it, and I think in a few weeks I'll have the same problem with Sapphique. There's just too much going on, and for me, too little empathy developed in the reader for the characters for the novel to stick with me.
That's not to say there's no fun to be had while listening. There's a lot of mystery, and it's rewarding to pick up on small new pieces of information along the way. The unlikely pairing of Keiro and Attia provides for some interesting adventures, especially as they are more fun than the more whiny Finn and Claudia.
The audio narrator, Kim Mai Guest, does a decent job with the different characters' voices, which is especially important because the book switches points of view frequently. I was initially turned off by Attia's strong cockney accent (and Ricks, for some reason, has a cockney lisp), but eventually I got over it.
Fisher's series is full of interesting ideas, but there's too much happening to be fully invested in the worlds and characters.