The Legend of Korra - Book 3 (Change)
Episode 6: "Old Wounds"

DescriptionWhile Korra learns metalbending from Su Yin, Lin goes through an acupuncture to deal with her repressed feelings, which reveals more of her backstory and of the difficult relationship she and Su had had for thirty years. In Republic City, Zaheer, Ghazan, Ming-Hua and P'Li escape inside a truck and intend to ascertain the Avatar's whereabouts...