I would agree with the other reviewers that this is a more thoughtful, maybe darker book than the previous ones. There's little lightness, no smiles or happiness, it starts grim and keeps on going, with an impressive body count. Add to that Jane feeling, and being, very much alone at the beginning, and you have a dark book. However, once I'd accepted that this was the case, I quickly got hauled in. DO NOT, as I did, look at the ending before you get there (I know, I know, a reeeeally bad habit I need to kick) - it could seriously mislead, and flavour how you read the rest of the book - so DON"T DO IT, 'kay?
There's a terrible, awful betrayal that made for uncomfortable reading and left me feeling quite disturbed and angry. It has ramifications that run through to the end, and into the next book. I now know very clearly who I rate and who I don't.
I liked the addition of the Younger brothers; they provide Jane with two people who are hers alone, and who she can trust, and the interactions between the three of them bring a little light relief to things. Rick reappears, and his scenes with Jane (and with Beast) are lovely, but sad. Jane spends a lot of the action as part of a team run by others which is unusual for her, and the outcomes suggest she's right to not trust to others to organise things, but she reverts to form for the end, and what a humdinger that is.
The next book is under way, and I see from the author's website that she's been contracted for a 9-book series, so Jane is around for a bit yet, yay! I just hope she manages a little fun and warmth and peace along the way.