This follows the last "Prey" book by one year....far too long in my opinion.
Lucas Davenport's adopted daughter, Letty, befriends a female "traveler" in California. Travelers are young homeless who wander the country usually following a rock band. In this case, they are following a group known as the Insane Clown Possee. Their followers dress up with face paint as clowns and are called Juggalos.
Letty is contacted by this girl who tells her that she thinks someone has killed her travelling companion. The suspect is a cult leader called Pilate who has a group of travelers that are into torture murders. She strikes out to follow this group seeking revenge and Letty follows her. Of course, Lucas is not far behind once he finds out that Letty is off on her own.
The plot quickens as Lucas starts chasing this group and it ends up in a massive shoot out. Once they get to the second Juggalo concert, the action is non stop and you will not be able to put it down. Fair warning....do not start reading that part late at night.
Definitely one of the better books in the series and it ends with an interesting twist.