Love, duty, and danger collide in Edwardian London, as the Shadowhunters face the greatest threat they have ever known.

Cordelia Carstairs, a Shadowhunter trained to battle demons, travels with her brother to London where they reconnect with childhood friends but soon must face devastating demon attacks in the quarantined city.

To save her mother's life, Clary must travel to the City of Glass, the ancestral home of the Shadowhunters -- never mind that entering the city without permission is against the Law, and breaking the Law could mean death. To make things worse, she learns that Jace does not want her there, and Simon has been thrown in prison by the Shadowhunters, who are deeply suspicious of a vampire who can withstand sunlight. As Clary uncovers more about her family's...

Someone is murdering Shadowhunters, provoking tensions between Downworlders and Shadowhunters that could lead to a second, bloody war. Clary's best friend, Simon, can't help her -- his mother just found out that he's a vampire, and now he's homeless. When Jace begins to pull away from her without explaining why, Clary is forced to delve into the heart of a mystery whose solution reveals her worst nightmare: she herself has set in motion a terrible...