Batman and Robin battle the Cluemaster; meanwhile, Aunt Harriet discovers the secret entrance to the Batcave. The Elongated Man wants to donate his old costume to Central City’s Flash Museum, but it’s been stolen.
"The Cluemaster's Topsy-Turvy Crimes!"
While trying to keep their secret identities from Aunt Harriet after she stumbles onto the secret passage to the Batcave, Batman and Robin also have to contend with the Cluemaster's attempts to trace the Batmobile back to the Batcave.
Batman and Robin are able to confuse the Cluemaster, making him think two other men are the dynamic duo, and then later bring him to justice for his crimes. Bruce Wayne and Dick Grayson then doctor a film that Harriet made of them entering the Batcave making it appear that Batman, Robin, Bruce Wayne, and Dick Grayson were all together and therefore are different people.
"The Case of the Costumed-Made Crook!"
The Elongated Man plans to donate his old costume to Central City's Flash Museum only to discover it has been stolen.