The world has been living in peace for a while and Sokka and Katara return to the southern water tribe to visit and Aang,Toph,Zuko,Momo,Appa come.It turns out a fire bender was in a time capsule who was then tries to fight them but everyone falls in the time Capsule and wakes up 2000 years later and Aang looses his memory about bending so must relearn bending to return to normal time period.