"Professor Supermind and Son" was a comic book feature that appeared in issues 60–71 (February 1941 — January 1942) of Dell Comics' Popular Comics publication. Professor Warren (Supermind) used his energy machine to give his son, Dan, superhuman powers, including super strength, invulnerability, and the ability to fly. With these powers, and his father's other inventions, Dan Warren fought criminals and Nazis.
Supermind's son was an obvious Superman knockoff, with a name similar to Superman, the same super powers, and, on some Popular Comics covers, a very similar blue and red costume(differing from the green, yellow, and red costume depicted on the pages inside). Despite this, there is no public record of Superman publisher DC Comics having taken legal action against Dell, as they did against some other publishers of characters closely modeled after Superman.