Our pal Ben Tennyson has been through a number of changes through out the years, even beyond the ability to shape shift into various alien forms. One of the most damaging, which occurred between the Ben 10: Alien Force and Ben 10: Ultimate Alien era, was having his secret identity exposed to the world. Now, wherever he or one of his alien forms goes, everyone knows who is really beneath it all. But then, somehow, Ben shoots over to an incredibly similar, but different Earth. Here, in New York City, there appears to be an alien threat that Ben must deal with, along with Humungousaur, Lodestar, Diamondhead, Rath and others. The problem is, no one recognizes the alien forms. Worse yet, no one recognizes Ben. …and who the heck is this Generator Rex guy…?