(3 years post-series) After a terrible fight with Katara, Aang flies off and doesn't return... for 5 years. At last, driven by love, regret, and a message from a mysterious stranger, Katara sets out on a journey to save him that will take her to the Spirit World and back. Meanwhile, Azula has escaped prison, bent on revenge. KATAANG! (w/some Zutara). Mild violence, language, & sex.