City of Glass: The Mortal Instruments, Book 3 Book Poster Image

City of Glass: The Mortal Instruments, Book 3



Exciting, violent series cycle concludes with a bang.
Popular with kids

What parents need to know

Educational value

Readers can think about how the author's version of vampire, werewolf, angel, and fairy lore differs from other books, and how it's the same. They'll also find quotes from the Bible, Milton's Paradise Lost, and Shakespeare's Twelfth Night tied into the section heads. Fantasy fans will race through this installment and be on to the next book in the series before you know it. Could lead to some interesting discussions about book series, and the difference between fantasy and realistic violence. See our "Families Can Talk About" section for some ideas.

Positive messages

Some classic good versus evil stuff as a brother and sister fight against their power-hungry father. The series also ponders what makes a family and binds people to each other. There's also an exploration of overcoming prejudice -- half-angel characters need to set aside their differences with other races (vampires, werewolves, fairies) to ensure their survival.

Positive role models

Adults, especially government officials, squabble and hold on to prejudices until the teen main characters set them straight. Clary and Isabelle are both strong female characters who fight for their families. Jace and Clary both show great heroism, especially when facing and fighting evil within their own family.


Lots -- throat slittings, decapitations, stabbings, bone-snapping, strangling, sword fights, injuries and deaths of major and minor characters, including inter-familial killings and killing of children. An angel, tortured for years with horrible results, commits suicide, a living man's heart is ripped out, semi-human creatures are tortured, a monster attempts to rape a girl.


Some passionate kissing and making out in bedrooms with shirts coming off, a character is gay and kisses a man, two other characters have what they (and readers) believe to be an incestuous relationship -- love is professed, but not acted on.


"Bitch," "bastard."


Video game, car, soft drink, snack food brands mentioned.

Drinking, drugs, & smoking

Teens drink wine in one scene.

Parents Need to Know

Parents need to know that there's lots of bloody violence, including lots of killing and injuries -- see content grid for details. There's also some kissing and making out, a major character is gay, and there's a relationship that appears to be incestuous. Some parents may be bothered by the religious aspects of the story -- angels and demons exist, an angel is tortured and commits suicide, another angel is summoned by a human, and the Shadowhunters have a mandate from God to kill demons.

What's the story?

In this conclusion to the Mortal Instruments trilogy (the conclusion to the first cycle of three anyway), Clary makes her way to the hidden Shadowhunter country of Idris, seeking a cure to her mother's magical affliction. While there, her father delivers an ultimatum to the Shadowhunter ruling council: declare him their leader, or he will use the Mortal Instruments to unleash a plague of demons and wipe them out. Meanwhile, Clary struggles to learn how to use her unique powers, discover her secret heritage, and figure out her relationship with her maybe-brother, Jace.

Is it any good?


Derivative, predictable, and melodramatic can be good things when they're played for fun and done well, and this is done really well. Action, horror, complexity, romance, twists that aren't too hard to see coming, mysteries the reader will figure out before the characters -- they're all here, in just the right amounts, and mostly with just the right pacing, though, like most 500+ page books, it sags in places.

It's easy to find things to criticize: the climactic battle happens offstage; the religious and incestuous aspects may disturb some; there's a fair bit of repetition. But with characters who grow ever more satisfying, a cleverly detailed fantasy world, a thoroughly engrossing writing style, and a host of questions from the earlier books answered before the end, fans of the series will find this everything they had hoped for. And if you haven't read the first two books? Don't even think of trying this.


Families can talk about...

  • Families can talk about the classic creatures used here. Why are vampires and werewolves always popular? How are they different here from the Twilight series?

  • Families can also talk about the violence in this book, and the whole series. Books 2 and 3 are especially bloody. Do you think the fantasy element makes the gore easier to handle?

  • The series seems to neatly end here, yet the author released a fourth book (part of a second cycle of three) and a prequel series -- starting with Clockwork Angel -- besides. There's also talk of a movie deal. Do you think more is better, or would you rather the series ended here?

Book details

Author:Cassandra Clare
Book type:Fiction
Publisher:Margaret K. McElderry
Publication date:March 1, 2009
Number of pages:541
Publisher's recommended age(s):14 - 17

This review of City of Glass: The Mortal Instruments, Book 3 was written by

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Teen, 14 years old Written bylovesateddybear November 10, 2010


Adult Written byrebekahF July 16, 2011

A fantasy world that I would LOVE to live in!

I didn't think i was going to find a series BETTER then the Hunger games until this series came along! From the start, it had me hooked! I fell in love with Jace and Clary, and *spoilers* i KNEW that it was going to work out for them in the end! This book is just as exciting and just as suspenseful as Hunger Games, and i never thought i would find another book like that! If you haven't read these books: read them. NOW. You won't regret it! and don't listen to people who say there is too much sexual tension blah blah blah and cussing. Who cares! what kinda book would it be if it didn't?! These are teenagers reading these books, not 5 year olds! trust me, they have seen MUCH worse! I thought the series was over after this book until i did some research and found out that there were 3 more books to come! AMAZING! You will fall in love with this book series, i guarantee it!
What other families should know
Great messages
Too much sex
Too much swearing
Teen, 13 years old Written bypoe-ette December 30, 2011

A rollicking, action-packed read...

For all you lame homophobes out there: Being gay is OK i SWEAR! Go read a bible if you can't handle it. Yeesh. (no offense to Christian people). Amazing book though. Read it on a couch with hot chocolate and a fire blazing in the mantle...
What other families should know
Educational value
Great messages
Great role models
Too much violence


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