Zim dreams of greatness. Unfortunately, though, hes hopelessly inept as a space invader. Desperate to be rid of the annoying Zim, his planets leaders send him on a mission to infiltrate Earth, providing him with leftover, cobbled-together equipment. To their consternation, Zim succeeds in setting up a base on Earth and infiltrating human culture, posing as a human child as he plots the planets downfall. Only Zims archnemesis, Dib, recognizes that Zim is an alien, and of course, nobody believes Dibs claims.