Cartoon Network is one of the titans of animation, with the cable channel introducing some of the most beloved animated properties of the past few decades. While the network originally started as an outlet for Turner Broadcasting to air its backlog of animated properties, including the iconic catalogue of Hanna-Barbera, Cartoon Network eventually took a turn to original programming. Early programs like Space Ghost Coast to Coast, Dexter’s Laboratory, Johnny Bravo, and Cow and Chicken helped define the company as the home of edgier, zanier cartoons than rivals like the Disney Channel and Nickelodeon, a legacy that has continued for decades since Cartoon Network’s inception.
While tons of iconic shows have flourished throughout the years at Cartoon Network, some haven’t been treated as nicely. Programs like Adventure Time and Regular Show still receive lots of love years after their original cancellations, in large part due to their still-existing fanbases. However, tons of cancelled Cartoon Network shows have fallen to the wayside, including these four that still haven’t gotten sequels.
Animated superhero projects have been around for decades, and while ’90s shows like Batman: The Animated Series and X-Men: The Animated Series are considered to be some of the best of all time, the best of the 2000s is easily Cartoon Network’s Teen Titans. The series created the most iconic iteration of the DC Comics superhero team, with the roster consisting of Robin, Starfire, Cyborg, Beast Boy, and Raven. Beginning in 2003, Teen Titans ran for five seasons and a movie, and was cancelled in 2006 for unclear reasons.
The Teen Titans brand has continued in the even more popular spinoff series Teen Titans Go!, but the original series has never been directly continued. This is a tragedy, as Teen Titans was more focused on serialized storytelling than its spinoff, meaning that we no longer get to see fleshed-out character arcs with these beloved characters. What makes things even more infuriating is that a Teen Titans continuation was teased at the end of Teen Titans Go! To the Movies, only for this teased return to merely culminate in the direct-to-video movie Teen Titans Go! vs. Teen Titans.
Genndy Tartakovsky is one of the most influential creative forces at Cartoon Network, having created programs like Dexter’s Laboratory, Samurai Jack, and Adult Swim’s Primal. Unfortunately, not all of his shows have been as popular as these. Case in point: Sym-Bionic Titan. Premiering in 2010, the series tells the story of three aliens who escape a takeover of their home planet and hide out on Earth, disguised as three high school students. However, their presence draws a lot of trouble, with the trio forming a massive cyber-giant in order to defend Earth from extraterrestrial attacks.
Sym-Bionic Titan is incredible, with it being just as good as Tartakovsky’s other action cartoons. However, the sci-fi series didn’t last long, as it was cancelled after its first season for failing to secure a toy line. Tartakovsky had begun work on 10 more episodes before the show’s cancellation, with these stories set to follow up on the season one cliffhanger. Unlike Samurai Jack, Cartoon Network hasn’t given Sym-Bionic Titan a chance to wrap up its story, with no more episodes being produced since its original ending in 2011.
The Grim Adventures of Billy & Mandy began as half of the two-segment show, Grim & Evil, which premiered in 2001. The series lasted much longer than its sister show, Evil Con Carne, with it becoming its own series in 2003 and running until 2007. Created by Maxwell Atoms, the series tells the story of two young kids who force the Grim Reaper to be their friend after beating him in a limbo contest, leading Billy, Mandy, and Grim to go on all kinds of twisted supernatural adventures together.
The Grim Adventures of Billy & Mandy was one of the most popular and influential shows at Cartoon Network in the 2000s, which is why it’s so shocking that it hasn’t returned in any form. According to Atoms, current Cartoon Network president Michael Ouweleen told Atoms that The Grim Adventures of Billy & Mandy was responsible for “ruining Cartoon Network’s brand,” leading to the show being cancelled as the channel went through a major creative overhaul headed into the 2010s. This explains why the series hasn’t returned, even if it helped define animation in the 2000s.
Another one of the most popular Cartoon Network shows of the 2000s was Codename: Kids Next Door, which tells the story of a group of secret agent kids who work with a massive underground organization in order to defend the world from adults. The series premiered in 2002 and ran until 2008, with it consisting of 81 episodes and two TV movies. There was seemingly no drama surrounding the show’s cancelation, with it simply running its course and coming to a natural ending.
For series creator Mr. Warburton, however, this wasn’t enough. Throughout the years, Warburton pitched a project to Cartoon Network titled Galactic Kids Next Door, although it was never picked up. So, on March 19, 2015, an animatic pitch for Galactic Kids Next Door was released online, getting fans excited about the idea of a sequel series.
Unfortunately, the sequel never happened. Galactic Kids Next Door has mostly faded out of the public eye, and with it, our best chance of a Codename: Kids Next Door sequel. While the world of the series is perfect for expansion, it seems unlikely that a sequel series will ever happen at this point.
What Cartoon Network series would you like to see return? Let us know over on the ComicBook Forum!


