The premise here is that October is investigating the sudden appearance of goblin fruit on the streets, which is highly addictive to changelings and humans, so addictive it kills them. Once she has proof that multiple changelings have died from the addiction, she goes to the Queen of the Mists to get help with the problem . . . and is promptly banished from the realm, given three days to pack up and ship out. Now she's scrambling to save herself from eviction from faerie completely, her allies banding behind her, and the only option may be to depose the Queen.
Again, the quality of the books has increased steadily and this book was solid. The characters are, once again, engaging and the plot moves along at a swift pace. In earlier books, the plot and some of October's decisions were . . . well, rocky and sometime didn't make sense. Not so here (or in the previous few books). Seanan appears to have completely settled into this world and this character. Probably the best part of this book is how October finds her allies supporting her in her efforts, all of the actions in previous books coming into play to help her achieve her goal. Also great, October doesn't wallow in angst and being alone, nor does she hesitate to accept the help she's offered. In past books, she'd refuse help or shove it to one side, which was always annoying. As a character, she's grown, and this book brings all of that growth to the forefront. Also nice, some of the plot threads that were alluded to in previous books (such as the goblin fruit being a problem on the streets, and multiple other side comments) are finally pulled together and addressed. Not all of them, and there's obviously some loose ends in this book that need to be tied up, but many of them come together here.
So, overall, a great book in this series. One or two minor things were overplayed (the kissing of Tybalt got slightly annoying and also the reliance on the Luideag in the first part of the book) but those were, as I said, minor. I'm looking forward to the next book in this series, which should be out sometime this fall.