City of Ashes by Cassandra Clare

In City of Bones : Book One of The Mortal Instruments Series, The reader is introduced to Clary, who discovers she's a Shadowhunter. In order to find her missing mother she embarks on a quest to find one of the mortal instruments before Valentine, a rogue Shadowhunter does. Along the way the tangled web of lies that Clary believed begins to unravel, bit by bit.
     In City Of Ashes : Clary attempts to live a normal life once again but when Jace gets into trouble, she is once again drawn toward the supernatural world and into the quest to once again stop Valentine from using another of the mortal instruments and its power. Along the way, not only does Clary and her friends and family change, some more than others, and some secrets to Valentine's past come to light, and other secrets are hinted at, just enough to keep the reader wanting more but not leaving them disappointed.