Five years after the original series, 15-year old Ben Tennyson must put the Omnitrix back on to rescue Grandpa Max from a new foe: the Highbreed, their DNAlien servants, and the Forever Knights. Unable to complete this task by himself he is joined by his cousin Gwen and a reformed Kevin. Along the way they meet other Plumbers kids who had powers like Bens previous alien forms and help Ben, Gwen, and Kevin fight the DNAliens.