In this case, the old friend is Melissa Marr, and she's woven a rich, dark and beautiful tapestry in Darkest Mercy (HarperCollins, Feb 22, 2011, $16.99, ages 12 and up), the final volume in the Wicked Lovely Series.
If you love the urban faerie world that Marr created starting with the first book, you will love the way she brings it all together in this volume. Finally, you will learn what happens to Ash, Seth, Keenan, Donia, and Niall. That may seem like too many points of view to handle, but Marr's sure hand never falters as she weaves together threads from all the previous books and interlaces each of the five main characters' stories. How she manages to make you care about all of them, I'll never know.The pacing is perfect, the atmosphere is dramatic, and as always, the writing is gorgeous.
Can't say much about the story without spoiling the plot. But I can tell you this: War is coming. Bananach, the Faerie of Discord, is gaining followers, and attacking other faeries. Can the Summer Queen, the Summer King, the Winter Queen, the Dark King, and Seth, newly-turned fey, find a way to work together to defeat her?