The Final Four (Avatar, the last airbender)

Centuries have passed since Korra was killed by the Organization called Control. The Organization wiped out all benders and sealed away the spirit of the Avatar in an item, traping the spirit of the avatar in the spirit world. However before Korra died, she used her energy bending on four non-benders and used it to send her bending down the line of descendants, until centuries later four people would awaken, each with their own bending ability. And that time is now. It's time to awaken, Final four.