As Korra tries to restore the streets of Republic city, she learns that her decision to keep the spirit portals open has created a new conflict between humans and spirits, and triggered the emerging of new Airbenders.
As Opal leaves for the Northern Air Temple to start her airbending training, Zaheer and his gang try to kidnap Korra. Although Korra's friends are able to prevent this following a climactic fight, they suspect that someone inside Zaofu has been aiding the enemy.
While en route to Ba Sing Se, Korra and Asami manage to escape from their cell, but their attempt to take control of the vessel results in the vessel losing altitude and hitting the sand. In Ba Sing Se, the Red Lotus hands over Mako and Bolin on condition that they get Korra, and the Earth Queen agrees. Meanwhile, Lin discovers the abandoned Jeep and radios Tonraq to rendezvous at the Misty Palms Oasis.
While Korra is struggling with PTSD by the metal poison Zaheer injected in her, she sets off on a journey to try to connect with Raava. Amidst all of this, Tenzin and the others realize that Korra has gone missing after 6 months.
Wu begins his exile with Mako's family, and realizes that he knows nothing about his bodyguard. So Mako tells him the story of how he met Korra and their relationship since then, effectively catching the audience up from book 1- now.