This book was quite lousy. I mean, the first in the series was fine but a bit messy, the second was a nice improvement, but this goes a step backward.
The story, overall, is not too bad, which is why I won't rate this with one star. Unfortunately, there are several weak parts, in which things just happen without much sense. The word I would use for this is convenience. For example, it was so convenient that, at a certain point, Alias remembers a detail about something that had happened before, a detail she wasn't able to notice before but now she is because she is no longer worried about Nameless (yes, that is exactly the explanation).
It strongly reminds me of a gaming adventure where the DM dispenses details as fits the game. Which, let's be honest, is probably the very truth. I am quite convinced that this book is the literary transposition of an AD&D adventure played by the authors.
Per se, that would not be a problem, but the fun in gaming sessions and the fun in reading follow different rules, so probably some reworking would have been in order.
The other drawback, and probably another consequence of being the transposition of a game adventure, is that the characters are terribly flat. I am quite aware that even very good role players might still not be good ad giving depth to their characters, so it is one explanation. The other explanation is that Mrs. Novak and Mr. Grubb (who, by the way, is a magnificent game designer) hadn't improved their writing skills so far.
Also, the novel becomes a bit confused at times. Just as it happens when there are many player characters divided in several groups (yes, I can't get this picture off my mind), it is a bit hard to track them consistently. A good DM might do that very smoothly, but that does not necessarily fit clearly into a novel.