On-sale date from ad in 80 Page Giant Magazine #9.
Inker credits from Nick Caputo (2006-9-28), originally given to Joe Giella.
This is the first Earth-1 appearance of the Riddler. This story references both the first story in Detective Comics #140 and the first story in Detective Comics #142, but those stories featured the Riddler of Earth-2. It should therefore be inferred that similar events happened on Earth-1 too, as depicted in the flashbacks shown in this story.
Credits for script and inks confirmed from Julius Schwartz's editorial records, provided by DC Comics. Records show that Bob Kane was paid for the pencils, but scholars agree that pencils were actually by Moldoff.