One of the greatest comic book titles, back in the day Mystery Men was a synonym for super-heroes. Mystery Men Comics #9 (April 1940) was published by Fox Feature Syndicate and inlcludes Lou Fine art of Rex Dexter on the cover.
Who is Rex Dexter? Dick Briefer created the character as type of a Flash Gordon or Buck Rogers. Rex’s origin starts in 1939 during the New York City World Fair when his father, Montague Dexter, demonstrated his Mars Rocket by flying with his wife to the red planet. Unfortunately, upon arrival the ship crashed and left Montague and his wife stranded there. Over the next sixty-one years they gave birth to Rex and the family worked to repair the ship. In the year 2000 Rex triumphantly traveled back to earth. Rex earned fame and fortune from his exploits as well as the affection of an Earth girl named Cynde who he had rescued from space pirates. Rex and Cynde went on to have adventures traveling through space visiting planets and saving Earth from multiple attacks by various menacing space invaders.
Mystery Men Comics also contains the first appearance of another early comic-book superhero, the Moth. Created by artist Jim Mooney the character’s only superpower was flight, presumably enabled by delicate moth-like wings. The stories never contained any origin explanation, but the Moth was able to successfully thwart the schemes of several mad scientists. Like a moth drawn too close to the flame, the character fizzled and after just four episodes was never heard from again.
Of note, interior story Billy Bounce (about a child who tries to be a detective) was scripted by Fred Schwab.