Clary Fray has learned yet more about her past and her true origins by the time the fast action brings readers to City of Glass. Her mother is still in a coma, but someone has pointed her in a promising direction that can help revive her. Problem is, that direction leads to the homeland of the Shadowhunters, Idris. Clary is excited about the prospect of traveling there, but Jace is dead set against her making the trip. When events conspire to keep her from going with the group from the New York Institute, Clary manages to get herself into the city anyway. But in doing so, she enters illegally and puts herself in even graver danger.

The Shadowhunters are trying to figure out how to defeat Valentine, who is going to come to the city and destroy their way of life. Clary’s “uncle” Luke has a plan that could make a big difference in who wins, but disagreements within the Clave could make it easy for Valentine to defeat them with his army of demons.

City of Glass is just as action-packed as the previous two Mortal Instruments books, and it introduces more mysteries into the story line. But very satisfyingly, it answers the mysteries that have been brought up throughout the series and brings the story to a conclusion of sorts. Cassandra Clare does her series justice in this third book, allowing her characters to continue to live and breathe and grow. The action is great, the interactions between the characters are real and often entertaining, and the plot is good and thick.

Rated: Moderate. There is some mild and moderate language, but Clare continues to refer to characters “cursing” sometimes without actually using the bad language. What makes the book a moderate (at least for teen readers) are two things: first, the level of violence and gore. There’s a lot of bloodshed, often of Downworlders and demons, but also sometimes of humans. Second, the teens in the book have been thrown into an adult world of lots of responsibility, but they’re also kind of free to run a bit wild. Young characters, whether they be Shadowhunters or Downworlders, drink alcohol and sometimes talk about sex rather freely. There are no details, and they don’t necessarily seem to be having sex, but they are talking about it pretty matter-of-factly without considering any of the consequences. There are also some homosexual characters.