Blue and her Raven Boys, Gansey, Ronan, Adam and Noah are all dealing with the consequences of the ley line ritual, particularly Adam. The ley lines have been awakened, but they seem to be out of control, and no one knows exactly why.
Noah keeps disappearing, Adam is off-kilter, Ronan confesses a huge secret, and Gansey is still trying to track down Glendower, all while trying to hold everyone together. All of our characters have family issues going on. Also, there's a hit-man in town looking for the Greywaren.
The group is now charged with fixing the ley lines, finding out what the Greywaren is and keeping it out of the hands of very bad people, and continue searching for The Raven King.
We learn a lot more about our characters' background in this story, and there is definitely some character development--not all of it good. New characters are introduced and I cannot wait to see what role they will all play in the next book.