In New York City, Clary Fray, a seemingly ordinary teenager, learns that she is descended from a line of Shadowhunters — half-angel warriors who protect humanity from evil forces. After her mother disappears, Clary joins forces with a group of Shadowhunters and enters Downworld, an alternate realm filled with demons, vampires, and a host of other creatures. Clary and her companions must find and protect an ancient cup that holds the key to her mother's future. When her mother disappears, Clary Fray learns that she descends from a line of warriors who protect our world from demons. She joins forces with others like her and heads into a dangerous alternate New York called the Shadow World.