Siegel and Shuster are credited with the Superman story in Action 81 (April 1945), the first story by them in this book for quite a while. If the credit is correct.
The story introduces Hocus and Pocus, a pair of wanna-be magicians. A few random coincidences convince them that they really have acquired magical powers, but also draw Superman’s attention.
Hocus and Pocus wind up joining up with a gang of thieves, wanting to pull off one robbery for the thrill of it, and believing that they could use their magic to return the money afterwards. Superman winds up helping them along, sometimes unintentionally, as he pursues the actual thieves.
At no point during the course of the tale do Hocus and Pocus figure out that they do not actually have powers, and decide to open up a detective agency, to make a profit off of them. Superman attempts to set them straight, but they simply don’t listen.
Hocus and Pocus would return a few months down the road, and be frequent supporting characters over the next couple of years.