In New Comics 9 (Oct 36) this Federal Men serial gets a name, The Invisible Empire. Although it ran from issues 4 – 10, only this chapter gets a title. The things we take for granted now were by no means a certainty then!
Steve infiltrates the underwater base, and the villains unleash giant killer robots!
Siegel and Shuster had been writing and drawing these kinds of stories since high school, but none of their previous published work had been allowed to venture into this territory. Even Dr. Occult, running in More Fun Comics, never had anything on this kind of scale. And the Superman concept they had been trying to sell was “too unbelievable” for comic books.
The Invisible Empire, although all but forgotten now, was almost as groundbreaking as Superman would be.