Korra and her friends hide in an underground homeless settlement until Iroh's fleet arrives, which is promptly disabled by Equalist mines and aircraft. After Korra saves Iroh from drowning, she decides to go after Amon with Mako. Infiltrating Air Temple Island, they find the captive Tarrlok, who reveals that Amon is his brother Noatak and also a bloodbender, driven to revenge on benders by their father Yakone who had fled Republic City after Aang captured him. Meanwhile, Korra's friends prepare an assault on the Equalists' mountain airbase to prevent the sinking of a relief fleet under Commander Bumi, Tenzin's brother.