This film is notable for three reasons.<br /><br />First, apparently capitalizing on the success of the two 'Superman' serials, this low budget feature was made and released to theaters, marking George Reeves' and Phyllis Coates' initial appearances as Clark Kent / Superman and Lois Lane. Part of the opening is re-used in the series. Outside the town of Silby, a six-mile deep oil well penetrates the 'hollow Earth' allowing the 'Mole-Men' to come to the surface. Forget about the other holes (those in the plot).<br /><br />Second, unlike most SF invasion films of the fifties, the hero plays a dominant (and controlling) force in preaching and enforcing tolerance and acceptance of difference against a raging mob of segregationist vigilantes. No 'mild mannered reporter' here! Clark Kent, knowledgeable and self-assertive, grabs control of the situation throughout ("I'll handle this!"), even assisting in a hospital gown in the removal of a bullet from a Mole-Man! As Superman, he is gentler than Clark towards the feisty Lois, but is also the voice of reason and tolerance as he rails against the vigilantes as "Nazi storm troopers." <br /><br />Third, you will notice that the transition from the Fleisher-like cartoon animated flying of Superman in the two serials to the 'live action' flying in the 'Adventures of Superman' had not yet been made.