The series takes place a year after the events of Ben 10: Alien Force. Ben Tennyson (voiced by Yuri Lowenthal) is now 15 years old and has become a superhero, known as Four Arms, thanks to his alien transformations. However, his life is turned upside down when a mysterious being known as "The Creator" reveals that Ben's ultimate form, the "Ultimate form," is actually a threat to the universe.