One of the greatest cartoon television series of all times became what may be one of the most disappointing films of all time a few weeks ago. Yes, I’m referring to Avatar: The Last Airbender, re-dubbed The Last Airbender for the M. Night Shyamalan film adaptation.

The award-winning Nickelodeon television series ran for three full seasons, designed that way intentionally to tell the full story of the legend of Aang, a young Airbender and the last of his people who, with his friends, must journey through the Water, Earth and Fire nations to learn how to master all four elements and save the world from the tyranny of the Fire Nation.

The series aired from early 2005 to mid-2008 and spawned the beginning of a potential film franchise. Due to the cartoon’s critical success and mass appeal, despite the film’s failure to become a big box office hit or win over critics (read our review of The Last Airbender), the creators of the series Michael DiMartino and Bryan Konietzk knew that Nickelodeon would come asking for more and that’s exactly what they did. Now we have a new series in the works, currently titled Legend of Korra.

The spinoff series, which made headlines back in May when Nickelodeon copyrighted the name, is being created as a more mature show with a new lead character; Korra is the next Avatar, a female teenage Water Bender from the Southern Water Tribe in a series which aims to keep the same sense of fun and adventure as the original. Nickelodeon confirmed a few days ago that the follow-up series would begin airing next year.

The story of the Legend of Korra takes place 70 years after the ends of Avatar: The Last Airbender where Aang has now passed away and Korra must learn the fourth and final element from the new last airbender left in the world: Aang’s son, Tenzin.

In an interview with The Wall Street Journal, Michael DiMartino and Bryan Konietzk talked about the genesis of the show and revealed a few key details. First off, Tenzin is the son of Aang and – you guessed it – Katara from the original series.

There will be definite tie-ins between the two series but no details were revealed as to what characters may make return appearances. The new series largely takes place in Republic City, a new location devised for the new series, based on designs of 1920s era Shanghai and Hong Kong with some Western influences thrown in as well.  One concept art image for the series (shown up top) has been released for the series and it gives you an idea of what Republic City may look like.

In Republic City, there’s an anti-bending movement taking place and this is where we will start seeing some of the more mature themes of Legend of Korrai unfold.

Here are some answers from the creators to questions you might be wondering yourself:

Avatars tend to live very long lives, how come Aang has passed after only 70 years?

“Konietzko: You gotta keep in mind that he was frozen in a state of suspended animation for 100 years, so he kind of burned up some of his extra Avatar time.”

What motivated the change in gender for the new Avatar and protagonist of the series?

DiMartino: “It’s not so much about changing because we had Avatar Kyoshi before Aang. We’d established that the Avatar can be male or female and we just thought let’s explore one of those more in depth, because Kyoshi was a popular character with a lot of fans and it seemed like a great opportunity to not retread what we’d done with Aang, who was a great hero, we all loved him, but we really wanted to try something different. And we have so many great female fans out there, who really responded to Katara in the first series, we thought we have the fan base who are really going to enjoy seeing the Avatar be a female.”

Konietzko: “Mike and I, we love those characters too, and we’ve encountered countless fans who are male who really like those characters too. We just don’t subscribe to the conventional wisdom that you can’t have an action series led by a female character. It’s kinda nonsense to us.”

It’s a little sad to see our favorite heroes from Avatar: The Last Airbender become history, but at the same time, I am excited at the prospect of another series set in the same world from the original creators and same crews. At Comic-Con 2010 last week, it was also confirmed that composer Jeremy Zuckerman will return to do the music and sound for the series – another great bit of news!

If you haven’t seen it or don’t own the series yet, check our our review of Avatar: The Last Airbender Book 1 Collector’s Edition.

Follow us on Twitter @rob_keyes and @screenrant and tell us what you think about Avatar: Legend of Korra.

Sources: The Wall Street Journal, UGO

Thanks for the tip, Catrina!