The Secret World Chronicles is a contemporary superhero saga in which metahumans, government teams, and ordinary people face an invasion from another world and the conspiracy behind it. The series follows the ECHO heroes as the conflict widens, testing both their powers and their loyalties. Mercedes Lackey wrote the five novels with collaborators Cody Martin, Dennis Lee, Veronica Giguere, and Steve Libbey. Read the novels in numbered publication order; Echo One is a short-story anthology and sits outside this novel route.