Dan, Marucho and Shun get caught up in a war in another universe, teaming up with three new brawlers: the Neathian, Fabia, the new human, Jake, and the undercover Gundalian, Ren, to stop the evil Gundalian Protectors from destroying Neathia, and possibly Earth.
When 10-year-old Ben Tennyson discovers a mysterious watch, he gains the power to transform into a number of different aliens, each with awesome powers. Ben realises that he must use these powers to help others and stop evildoers, but that doesn't mean he's above a little super powered mischief now and then.
Beating the bad guys is just part of the superhero gig. With a little help from his new, by-the-book rookie partner, Ben explores the quirkier side of things in the alien underground and discovers enemies from his past looking for a re-match, all while a mysterious hunter is hot on his trail! With 10 new aliens at his disposal and a brand new lease on life, Ben 10 is back and more fun than ever!