Detective Comics #188

Batman and Robin stop a robbery at the waterfront. Shortly thereafter the criminal responsible sends word to Commissioner Gordon that he plans to kill Batman in the Batcave.

The first murder attempt happens when Batman and Robin return to the bat-cave and Batman's cape burst into flame from a slow-acting chemical that was poured on him earlier. Batman realizes that his cape had been tampered and removes it before it can harm him. The killer then tries a second time using the Batmobile's tires. While the Dynamic Duo were outside fighting crime, the killer switched the tires of the Batmobile for tires filled with knockout gas. Suspicious of the batmobile Batman stops the car before entering the batcave's garage, and the tires explode releasing the gas. Fortunately Batman noticed the different tires, so Batman and Robin were wearing gas masks when the tires blew.

Batman then receives a last threat indicating that the criminal has placed a bomb in the batcave and that it will blow up at noon next day. Batman and Robin search the entire Batcave for any bomb, but they find nothing. Desperate to find a clue, the Dynamic Duo capture the criminal who has been threatening them and take him to the Batcave, where they try to force him to reveal the location of the bomb. However, the thug doesn't know where the bomb is located and after his confession, Batman realizes that the thug is unknowingly carrying the bomb on his prosthetic arm. With great haste Batman deactivates the bomb in the nick of time.

After the whole situation has been cleared up, Batman deduces that the man responsible for the murder attempt is not the thug they just captured, but the man they saved at the waterfront robbery at the story's beginning. Soon after deducing the real villain's identity, Batman captures the real criminal and delivers him to the police.