"City of Fallen Angels" continues the story of Clary Fray as she navigates her life in New York, where she must confront the complexities of love and the looming threats from the Shadow World. As her relationship with Jace becomes more intense, they face challenges that test their bond. Clary must also deal with the repercussions of her newfound powers and the secrets surrounding her past, all while trying to maintain her normal life. The book introduces new characters and expands on the existing ones, exploring their struggles and motivations. Clary's friends, including Simon, find themselves entwined in the supernatural conflicts, further complicating their lives. The dynamics between characters shift as loyalties are tested and old rivalries resurface.