Cassandra Clare was born to American parents in Teheran. She has traveled the world as a child and eventually ended up living in LA and New York. She has written various articles for entertainment magazines and tabloids. For more information about her you can visit her website http://www.cassandraclare.com/cms/home.In the fourth book in the Mortal Instrument story, Clary Frey is back in New York. She is receiving Shadowhunter training. Her mother is about to get married to Luke. She can finally call Jace her boyfriend.But someone is killing Shadowhunters in New York. The Clave is investigating it but it seems our young friends are more involved in this situation than they wished for.Simon left home after his mum found out he is a vampire. On the street all the groups of the 'magical' world are trying to get him to join groups with them. Then there is the situation of his love life, dating two girls can become dangerous too.Jace is having terrible nightmares and is trying to stay away from Clary as much as possible which she is trying to fight for all the obvious reasons. Will Simon find a place to stay? Will Clary manage to get Jace back? And who is killing the Shadowhunters? Just as the others in this series I find the book amusing but still not really special. For me it does not touch the same hype level as say Harry Potter or Twilight and the books will probably not pop up as an advice for adult readers. On the other hand, the pace and storyline of the book are entertaining. It makes for a nice read. The characters get more and more depth, specially Simon in this book. I am still much confused by the time line though. I cannot calculate how long the book is lasting. I found out in this book that the last book was covering about 2 weeks, but while reading it I did not have a clue. If you tell me this book was written over a timespan of two days I would go for it. There are some extra points for this book though for mentioning Lemmings.