The Legend of Korra (TLOK) begins 75 years after the Last Airbender(TLA). It follows Korra (from the Southern Water tribe) the 17-year-old Avatar. The plot begins with Korra, having mastered fire, water and earthbending, moving to Republic city to complete her airbending training. Her master is Aang's son, Tenzin. However, Republic City is amidst an anti-bender revolution, led by the mysterious Amon. Along the way she meets Mako and Bolin, orphan brothers who lost their parents to firebenders.
TLOK, much like it's predecessor, has beautiful animation and draws you into a fantastic world. Having one setting, without detracting from the plot, allowed the animators to flesh out the city. When compared to the TLA, the characters were weaker but the plot was considerably better, ignoring the last 3 episodes. Unfortunately, the ending, resulted in the series falling below the lofty standards of it's predecessor.
Korra was a vast improvement on Katara. She is strong, independent and genuinely engaging. Unlike Katara she is not overbearing. However her characterization was poor. I found that she was essentially the same character in the first and last episode. In fact most of the characters were left undeveloped.
Tenzin was a good character given the right amount of characterization. He is calm yet funny. However his children were quite annoying and given too much air time at the expense of the other characters.
Mako, the Zuko equivalent, was melodramatic. Initially he is cold and distant but by the midpoint of the series he is emotionally volatile. He is a highly advanced firebender, in my opinion far too advanced. One of the themes of the show is the love quadrangle involving Korra, Asami, himself and his brother Bolin.
Bolin, the equivalent of Sokka, is an earthbender. Unfortunately Bolin wasn't fleshed out as expected and was completely irrelevant.
Other characters include Asami, Mako's girlfriend, who proved to be one of the better characters. Again, she was not fleshed out enough. The little attention paid to her leaves her as the most compelling character. Bei Lin Fong, Toph's daughter, was head of the police. She is also capable of metal bending and overall is colder and less outgoing than Toph.
Finally we come to Amon, the most interesting character, until the finale. He believes that benders are oppressing the non-benders. Having had his parents murdered by firebenders he starts a powerful revolution. He is the most advanced fighter on the show and develops a deadly skill.
The plot was more complex than TLA. In Amon there is a villain whose goal, equality, is admirable. His action to achieve that goal are questionable. The build up to the last finale was superb. The series was about to surpass all expectations. However the final 2 episodes were rubbish. To sum up, the finale undid all the previous good work. The complex themes, heart rendering sacrifices and meticulous build up were wasted.
At the heart of it all, TLOK aimed to integrate adult themes into a children's story. This required a rosy ending that, unfortunately, detracted from the plot significantly.