The success of the Superman serials led to the release of the character’s first feature-film, titled Superman and the Mole Men. In the movie, George Reeves replaced Kirk Alyn as the hero, who proved to be a much better fit for the role. The movie paired the child-friendly action of the earlier serials and comics with themes adults could dig.
The movie put a spotlight on humanity's fear of those who are different, which echoed the racial conflicts of the time. This was an early example of superheroes entering the realm of the socially conscious. Like the serials, the movie was a hit and had a bigger impact on the character’s legacy than anything else before it. Its success was also instrumental in what came next.