Superman: The Mad Scientist (1941)

Directors: Dave Fleischer, Steve Muffati (uncredited)
Writers: Jerry Siegel (comic strip created by: Superman) (as Jerome Siegel), Joe Shuster (comic strip created by: Superman)
Stars: Bud Collyer, Joan Alexander, Jackson Beck

The Man of Steel fights a mad scientist who is destroying Metropolis with an energy cannon.
Trivia
In late 1942, the comic book Superman 19 featured the story "Superman, Matinee Idol" where Superman and Lois watch this cartoon at the cinema. The metaphysical fourth-wall-breaking nature of the story caused it to be relabeled "Our Very First Imaginary Story" in reprints.
Marks the first appearance on film of the famous introduction, "Faster than a speeding bullet", etc. . . . , and of the "Look, up in the sky,", etc. . . .
This series is where Superman "learned" to fly. Prior to this he was only able to "leap tall buildings in a single bound." It was deemed that leaping would not look right on film. However, even when Superman flies it looks as if he needs to make a jumping start, rather than just taking off.
Max Fleischer and Dave Fleischer were reluctant to take this assignment because it would require much more realistic designs and animation than they usually used. They tried to discourage Paramount by stating they would need a budget of around $100,000 per short, four times the budget of an average Walt Disney cartoon, which then had the highest budgets in animation. To their shock, Paramount executives agreed to at least half the amount, which made the Superman series--in adjusted dollars--the biggest-budgeted animation series in film history.
Model sheets were provided by Superman co-creator and illustrator Joe Shuster.
This short is often retitled "The Mad Scientist" on video release to distinguish it from other Superman cartoons.
Boris Karloff's character of engineer Poelzig in The Black Cat (1934) was the inspiration for the mad scientist in this animated Superman cartoon. His Mao suit, hairdo, the way he climbs down the spiral staircase only as a shadow, are obviously referenced in the cartoon as well as the organ playing by Karloff's mad scientist. These have all become horror-film staples.