City of Fallen begins with Simon and Isabelle on a date. While they are talking about Luke and Jocelyn's wedding, to subjugates come and force Simon to meet a vampire named Camille. When Simon goes and meets her, she asks him to join her to defeat Raphael. She gives Simon 5 days to decide. Meanwhile, Clary, Jace, Luke, amd Maryse find out there has been a recent string of dead Shadowhunters. When given the chance to talk to one, they find out someone named Camille did it. At one of Simon's band practices, a guy named Kyle auditions for the role of lead singer. He gets the part and allows Simon to move into his apartment. I hope Kyle doesn't turn out to be evil.