A comic book hero who did not fare well making the transition to radio was the Blue Beetle, whose show on CBS radio lasted only from May to September 1940, a total of 48 episodes. First created the year before by Charles Nicholas for the comic book Mystery Men, the Blue Beetle was actually police officer Dan Garrett, who went beyond the call of duty by donning a costume provided by a druggist friend to create fear in the hearts of criminals. The character moved into newspaper syndication while remaining a comic book staple before appearing on radio. The show usually had two thirteen-minute episodes per story arc an, for the first thirteen shows, starred Frank Lovejoy, after which the Blue Beetle was played by an uncredited actor (or actos?).
Over the years the Blue Beetle has been through many changes, revisions, and corporate owners, most recently in a 2008 comic in which Dan's last name has dropped its final letter and in which he is referred to as "Big Blue" -- the better to skirt copyright laws. In the 2012 film Agent Beetle, the character was never referred to as the Blue Beetle -- perhaps also due to those pesky copyright laws. And the character has been referenced in at least three DC Comics television shows, sometimes obliquely.
Enjoy these first two episodes of The Blue Beetle, "a friend of the unfortunate, enemy of criminals,a mysterious all-powerful character...a crusader for law."