The Green Hornet and Kato are in Gotham City to bust a counterfeiting stamp ring. Believed to be arch-criminals by nearly everyone, their midnight visit to Colonel Gumm at the Pink Chip Stamps Factory stirs alarm. Even Batman and Robin believe they are out for a piece of the action. Figuring the Green Hornet's goal must be the Gotham Gothic, a rare and valuable stamp, they trail him and Kato to the Pink Chip Stamps Factory. But when Colonel Gumm and his men make giant stamps out of the visiting crime fighters, it appears Batman and Robin will be doomed to the same fate.

Colonel Gumm moves out of the Pink Chip Stamps Factory, taking its owner Pinky Pinkston along as a hostage. A message hidden by Miss Pinkston in a bowl of alphabet soup directs Batman and Robin to the International Stamp Exhibition. Though the Green Hornet and Kato will be attending to try to expose Colonel Gumm, Batman and Robin believe they are out for personal profit. The misunderstanding has the two sets of crime fighters fighting each other while the real criminal nearly makes off with the exhibition's rare and valuable stamps.