Suddenly able to see demons and the Darkhunters who are dedicated to returning them to their own dimension, fifteen-year-old Clary Fray is drawn into this bizzare world when her mother disappears and Clary herself is almost killed by a monster.
As mysterious murders threaten the new peace between Shadowhunters and Downworlders, only Simon, the Daylighter vampire, can help bring both groups together.