This episode adds two never-before-on-the-show heroes: Mister U.S. (who has been previously seen in comics from Image Comics and About Comics, among others) and Blacktop. Plus, the world's richest kid, and there's some problem with lunch. And as usual, your favorite hero team call center workers! Guest voices: Jeremiah Dobles, Ben Bradt, and especially Melvin Ishmael Johnson. Written by Nat Gertler. Invisible Zeppelin is a production of About Comics.