This is definitely not a stand alone book. The convoluted plot laid out in the first two books is only somewhat resolved in the last one, but is complete nonsense if you only read the third book by itself. I learned that first hand when I received a free copy of this book from the publisher and attempted to review it without being familiar with the series.
Disclaimer: I received a free copy of this book from the publisher for review purposes. I was not required to write a favourable review. The opinions expressed are strictly my own.