Ben 10 Alien Force begins the next chapter in the continuing Ben 10 saga five years later when 15-year-old Ben Tennyson chooses to once again put on the OMNITRIX and discovers that it has reconfigured his DNA and can now transform him into 10 brand new aliens. Joined by his super-powered cousin Gwen Tennyson and his equally powerful former enemy Kevin Levin, Ben is on a mission to find his missing Grandpa Max. In order to save his Grandpa, Ben must defeat the evil DNALIENS, a powerful alien race intent on destroying the galaxy, starting with planet Earth. Ben will join forces with other young heroes to save the galaxy and his Grandpa Max, while passing along his knowledge to a whole new generation. Ben Tennyson is a normal, well-adjusted teenager who has long ago put away the Omnitrix that gave him his powers. His adventures as a shape-shifting hero are little more than fond memories. Shortly after successfully defeating the alien menace of Vilgax, Ben learned how to remove the watch, and he hasn’t needed its powers since. The last thing on his mind was to get involved in another series of adventures, but that was before he discovers his Grandpa Max is missing.