Main article: Ben 10 (TV series)
As the original series, Ben Tennyson and his cousin Gwen Tennyson shared the same birth date, making them both 10 years old. Later chronologically they turn 11, with Grandpa Max being 59-60. This version of Ben was more childish, rude, and cocky. Dr. Animo, Vilgax, and Kevin 11, recurred through the series as main villains. The pilot episode aired on December 27, 2005, as part of a sneak peak of Cartoon Network's Saturday morning lineup. The second episode was shown as a special on Cartoon Network's Fridays on January 13, 2006. The final regular episode aired on April 15, 2008. A total of 52 episodes, spanned across 4 seasons were produced and aired.
Main article: Ben 10: Alien Force
Ben 10: Alien Force is the sequel to the original series set five years later, with Ben and Gwen being 15 years old. Kevin 11, a former villain of Ben and Gwen's now becomes an ally, replacing Grandpa Max (when he goes missing). As an indirect result, this series is darker in tone compared to its predecessor, featuring more complex plots and more characters dying. Major villains from the first series including Vilgax, guest star in various episodes. The series premièred on Cartoon Network on April 18, 2008 and ended on March 26, 2010. It has since been premiered in Canada, on Teletoon. Unlike the previous series, and the later sequel series, Cartoon Network ordered 3 seasons of the series, with a total of 46 episodes making the whole series. The series was originally entitled Ben 10: Hero Generation.
Main article: Ben 10: Ultimate Alien
Another sequel series, Ben 10: Ultimate Alien premiered on April 23, 2010 and takes place 3–4 weeks after the finale of Alien Force. Ben, Gwen, and Kevin have been announced to be aged by 1 year, making both Ben and Gwen age 16, and Kevin age 17. With a total of 20 episodes in its first season and 32 episodes in its second Ben 10: Ultimate Alien has been confirmed to hold 52 episodes. The series originally went under the title of Ben 10: Evolution.
A fourth series has been announced, and is under production. Yuri Lowenthal, Greg Cipes and Ashley Johnson will reprise their roles as Ben, Kevin and Gwen from Alien Force and Ultimate Alien.
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