Ben 10: Alien Force
After trying to test a broken teleporter pod, the team decides to enlist the help of Cooper Daniels, the young boy who had helped the Tennysons in the past. Upon reaching his home, they discover a video of his capture by the DNAliens. They track him down to the abandoned military base Los Soledad, where Paradox built his time machine. They discover that the Highbreed have erected a cloaking field, built by Cooper over the area, concealing a huge, mysterious arch-shaped device.