City of Glass Summary

Cassandra Clare

City of Glass

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City of Glass Summary

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City of Glass is the third novel in Cassandra Clare’s The Mortal Instruments trilogy, which follows the adventures of Clary Fray, a once-ordinary girl who discovers she is a Shadowhunter, a human-angel hybrid created to destroy demons. In the first book, City of Bones, Clary discovers her true nature and along with her best friend Simon, meets fellow teen demonhunters Jace, Isabelle, and Alec. Clary’s mother, Jocelyn, is a Shadowhunter as well, as is Clary’s estranged father, Valentine, who has turned evil and tries to kill Clary and Jocelyn in his search for the Mortal Instruments, powerful talismans. In City of Ashes, Clary and her friends investigate the murder of children who are Downworlders—otherwordly beings like werewolves, vampires, and faeries. She, Simon, and Jace become involved in a love triangle, despite the fact that Jace and Clary believe they are half siblings, Valentine being their father.

City of Glass opens with Clary making plans to travel to Idris, the City of Glass within Alicante, Spain, that is home base for the Shadowhunters. There, she will seek out a magician named Fell who can bring her mother, Jocelyn, out a self-induced poison coma. Jace, worried for Clary’s safety, tries to convince Simon to dissuade Clary. Before they can, they are attacked by Forsaken warriors, human-like monsters Valentine controls. Jace pulls Simon through a magic portal to Alicante, whereupon Simon is arrested on suspicion of being Valentine’s spy.

Clary learns of all this and creates her own portal. Once in the City of Glass, Clary meets Sebastian, an attractive young Shadowhunter, and confronts Jace, finding him embracing Aline, Sebastian’s pretty cousin. Clary, who still loves Jace, is angry. Jace is similarly angry at Clary for making her own portal. Sebastian takes Clary to meet Fell, the magician, but they discover he was killed by Valentine hours earlier. Another magician, Magnus Bane, offers to help Clary, telling her that the spell she needs is hidden in a book in Valentine’s house.

Clary tells Jace about the book and he agrees to help. They go to Valentine’s house, freeing a dying angel Valentine has kept captive. They retrieve the book and return to Idris, where they find Valentine and his demon army attacking the city. Jace breaks Simon out of jail. When the invaders retreat to recover strength, an alliance between Shadowhunters and Downworlders is proposed. Clary reveals that the dying angel taught her an ancient rune that will combine Shadowhunters and Downworlders in pairs, making them more powerful together. Using the spell from Valentine’s book, Magnus Bane awakens Jocelyn who reveals to Clary that she and Jace are not siblings.

Idris’ citizens prepare to fight. Jace goes in search of Valentine, whom he believes to be his father. On his way, he encounters Sebastian, who reveals that Jace’s father is not Valentine but another Shadowhunter. Sebastian, on the other hand, is Valentine’s son. Jace realizes that Sebastian is a spy for Valentine and fights him, eventually killing Sebastian.

Meanwhile, Clary portals to Lake Lyn to prevent Valentine from summoning Raziel, the father of all Shadowhunters. Valentine hopes that by summoning Raziel, he will be granted one wish. He will ask for Raziel to create a new race of Shadowhunters whom he can use to destroy the current Shadowhunters and Downworlders. Valentine paralyzes Clary, telling her that he will use her as a sacrifice in the summoning ritual. Jace arrives to rescue her, but Valentine kills him and uses his blood to summon Raziel, but not before Clary secretly adds her name to the runes used in the ritual. Raziel appears, but declares that Clary was the one to actually summon him, thanks to her rune switch, and he will grant her wish, not Valentine’s. Raziel kills Valentine, and Clary asks to have Jace brought back to life. Raziel resurrects Jace.

At a celebration celebrating the Shadowhunters’ victory, Clary and Jace declare their love for one another, relieved that their relationship is not incestuous. Clary celebrates with her friends and family.

As with the previous Mortal Instruments novels, a central theme in City of Glass is identity. Clary, a once average girl who is now front and center in a fight for her people’s survival, continues to grapple with her identity. Similarly, Jace discovers his own complex identity throughout the novel. Though he once buried his feelings for Clary, believing her to be his sister, the revelation that they are not related changes the way the two perceive one another and redefines what their relationship is and can become.