City of Glass

City of Glass is the third installment in the six-book Mortal Instruments series, following City of Ashes and preceding City of Fallen Angels. In City of Bones (the first installment), Clary (raised as a human—or “mundane”—by her Shadowhunter mother, Jocelyn, and her werewolf father figure, Luke Graymark) is introduced to the Shadowhunter world when her mother is kidnapped by her biological father, Valentine. Her mother uses a potion to put herself into an enchanted sleep to prevent Valentine from torturing information out of her. Clare uses the sleep potion as a plot device in both City of Ashes and City of Glass. Clary and fellow Shadowhunter Jace are attracted to one another from the moment they meet, which becomes complicated when they learn that they are siblings at the end of City of Bones. Ultimately, this turns out not to be true, but they grapple with their feelings throughout the second and third books until the truth is revealed toward the end of City of Glass. Sebastian (the real Jonathan) is Clary’s actual brother, and City of Glass sets him up as the main antagonist for the second half of the series.

The Mortal Instruments is a young adult urban fantasy series, set mostly in New York City, occasionally traveling to other—often fictional—locations such as Idris, the mythical Shadowhunter country. As often happens in urban fantasy, normal humans live alongside supernatural beings, never realizing vampires, werewolves, and other “downworlders” exist. Clare’s supernatural world has three classes of beings: Shadowhunters (a race of humans born with angel blood who fight demons), downworlders (part-demon creatures such as fairies and vampires), and demons (creatures of hell that feed on human life force). Long before the events of the series, Shadowhunters took up the angel Raziel’s mission to protect the world from demons, which allowed them to use runes for special protections and abilities in combat. In the story’s present, Shadowhunters believe themselves superior to downworlders because of their angel blood. Shadowhunters once hunted downworlders, but an agreement was struck among the governing bodies of the various races that granted downworlders protections against Shadowhunter abuses. Valentine, the main antagonist of The Mortal Instruments, opposes the agreement because he believes association with part-demon creatures taints the purity of the Shadowhunter race. As a result, Valentine works to purge the world of downworlders and of Shadowhunters who sympathize with them, by violent death if necessary.

The Mortal Instruments is one of several series in the Shadowhunters universe, all of which come together to flesh out Shadowhunter lore. As a warlock, the character Magnus Bane may live for hundreds of years, which makes him a common thread throughout the various series. He appears in The Mortal Instruments as a love interest for Alec Lightwood and an ally to the New York Shadowhunters. He’s also present in the Infernal Devices series (set in a steampunk version of London) offering support to the London Institute, as well as in the Dark Artifices series (set in California several years after Mortal Instruments) as Alec’s long-term partner. Shadowhunter families also play prominent roles in the different series. Jace is revealed to be a Herondale at the end of City of Glass, related to Will Herondale—one of the main characters of the Infernal Devices. Jace also appears in crossover works cowritten by Clare and young adult fantasy author Holly Black, whose fairy characters appear as downworlders in Clare’s Shadowhunter universe.