Great episode! Nice action!
We're back in Zaofu, as Korra and Bolin continue to learn Metal Bending, and Opal leaves for the Air Temple. In the night, Zaheer and his comrades try to kidnap Korra! The combined efforts of Bolin, Mako, Lin, Suyin, and the rest of the guards are enough to rescue Korra, but only barely. They determine that it must have been an inside job, and try to learn who could have helped the criminals. Aiwei, Suyin's adviser who can sense lies, questions the guards and says that one guard is guilty. However, the kids are not convinced. When Mako, Bolin, Asami, and Korra investigate, they find out that Aiwei was the guilty party.
Lin demands that Korra come back to Republic City, where she can be better protected. Suyin agrees that this is best, but then later helps Korra and her friends to get away without Lin's knowledge. They want to folow Aiwei and get to the bottom of this business with Zaheer once and for all.
This was a really succinct summary, and part of that is because the episode was so well-focused, and spent such a long time on action scenes that there really isn't a lot of detailed plot, or subplot, to account for. I really don't have a lot to complain about, though...