When Clary Fray witnesses three tattoo-covered teenagers murder another teen, she is unable to prove the crime because the victim disappears right in front of her eyes, and no one else can see the killers.
She learns that the teens are Shadowhunters (humans who hunt and kill demons), and Clary, a mundie (i.e., mundane human), should not be able to see them either. Shortly after this discovery, her mother, Jocelyn, an erstwhile Shadowhunter, is kidnapped.
Jocelyn is the only person who knows the whereabouts of The Mortal Cup, a dangerous magical item that turns humans into Shadowhunters.
Clary must find the cup and keep it from a renegade sector of Shadowhunters bent on eliminating all nonhumans, including benevolent werewolves and friendly vampires.
In Beatrice Prior’s dystopian Chicago, society is divided into five factions, each dedicated to the cultivation of a particular virtue—Candor (the honest), Abnegation (the selfless), Dauntless (the brave), Amity (the peaceful), and Erudite (the intelligent). On an appointed day of every year, all sixteen-year-olds must select the faction to which they will devote the rest of their lives. For Beatrice, the decision is between staying with her family and being who she really is—she can’t have both. So she makes a choice that surprises everyone, including herself.
During the highly competitive initiation that follows, Beatrice renames herself Tris and struggles to determine who her friends really are—and where, exactly, a romance with a sometimes fascinating, sometimes infuriating boy fits into the life she’s chosen. But Tris also has a secret, one she’s kept hidden from everyone because she’s been warned it can mean death. And as she discovers a growing conflict that threatens to unravel her seemingly perfect society, she also learns that her secret might help her save those she loves . . . or it might destroy her.