Avatar The Last Airbender - The Promise manga summary: Ever since the conclusion of Avatar: The Last Airbender, its millions of fans have been hungry for more - and it’’s finally here! Think of this as the Book Four (season 4) of Avatar because it continues Aang’s story from right where the TV series left off. This series rejoins Aang and friends for exciting new adventures, beginning with a face-off against the Fire Nation that threatens to throw the world into another war, testing all of Aang’s powers and ingenuity.