City of Fallen Angels by Cassandra Clare
City of Fallen Angels takes place two months after the events of City of Glass. In it, a mysterious someone’s killing the Shadowhunters who used to be in Valentine’s Circle and displaying their bodies around New York City in a manner designed to provoke hostility between Downworlders and Shadowhunters, leaving tensions running high in the city and disrupting Clary’s plan to lead as normal a life as she can — training to be a Shadowhunter, and pursuing her relationship with Jace. As Jace and Clary delve into the issue of the murdered Shadowhunters, they discover a mystery that has deeply personal consequences for them — consequences that may strengthen their relationship, or rip it apart forever. Meanwhile, internecine warfare among vampires is tearing the Downworld community apart, and only Simon — the Daylighter who everyone wants on their side — can decide the outcome; too bad he wants nothing to do with Downworld politics. Love, blood, betrayal and revenge: the stakes are higher than ever in City of Fallen Angels.
When I heard that Cassandra Clare was writing a fourth book in The Mortal Instruments series, I was estactic.This trilogy was one of my favorites and I can't wait to follow Clary and Jace around some more. Look for it in stores on April 5, 2011.