In this entry in the long-running series, the Bowery Boys must help a reporter who was beaten up during an undercover investigation at a local prison. With the consent of the reporter's editor, the boys pull off a phony jewel caper and two of them are imprisoned. In the pokey, they learn that the editor is the real thief and that they really are in prison. Hijinks ensue until they expose a scam surrounding prison guards on the take from inmates who pay them to give them easier jobs. This allows them to prove their innocence and eventually expose the evil editor.