Hawkman and Black Canary visit the home of ancient coin collector Fred Bain and nearly stop two members of the Invisible Band until Elmer Doolittle, convinced the duo are crooks, helps the real crooks get away. Meanwhile, at Gracy's Department Store, the Band has its eyes on the $1 million in receipts the store has taken in, but Dr. Mid-Nite and Wonder Woman put the squash on that until Elmer shows up and allows the real villains to escape. At an exclusive florist shop, GL is able to stop the Band from seizing the receipts from Sweetheart's Day until Elmer steps in and the crooks escape.; An incredible robbery of $50,000 from an oil company spurs the JSA to the conclusion that the Invisible Band is responsible. However, the charwoman who cleans the apartment the JSA meets in, discovers a sketch (by Dr. Mid-Nite) that looks like a puzzle, so she gives it to her nephew, Elmer, who fancies himself an amateur detective. He reaches the same conclusion as the JSA, so disguises himself to investigate the apartment, believing it to be the HQ of the criminals. When the JSA returns, he believes them to be the crooks dressing as the JSA and leaves to report this to his detective school.; Members of the Band successfully rob a bank during a Mardi Gras gala, then hide from the Police in a wax museum. The Atom and Flash discover the ruse and knock the Band for a loop until Elmer shows up and allows the Band to escape. Meanwhile, the JSA is being held prisoner by the Invisible Band, who gives Elmer his diploma IF he can put a bullet into seven targets on a stage. Elmer doesn't know that a JSA member is behind each target, but as he prepares to shoot, a stumbles, wild shots hit a water pipe, and the JSA gets free and cleans up the gang.