City of Fallen Angels is the fourth book in the The Mortal Instruments series by Cassandra Clare. The series was meant to end with City of Glass; it was announced in March 2010 that a fourth book would be added, with Cassandra Clare later saying that she views this as a "second trilogy" in the series. The book was released on April 5, 2011.
Simon receives an offer from a vampire named Camille Belcourt who claims to have been usurped by Raphael Santiago. She says that if Simon joins her side as the Daylighter, he will finally earn his place in the vampire society. After his meeting, he returns home worried about what his mother would think, as she has been suspicious since he went to Idris in City of Glass and did not return for a few days. Although Magnus Bane erased memories of his absence, she was still subconsciously suspicious about his whereabouts.