Synopsis: The Joker - a grinning clown-faced killer - announces his crimes over the radio, threatening to kill several men and steal valuable items from them. When he is successful, the underworld becomes angry that he has upstaged them. Brute Nelson, a gangster, plans a trap for the Joker, but the Joker avoids the trap and kills Nelson. Batman, having taken an interest in the case is nearly killed himself when he attempts to pursue the Clown Prince of Crime.
Batman has Robin watch the site of the Joker's next attack where the Joker kills Judge Drake. Robin follows Joker back to an old house, but is captured. Batman arrives in time to save Robin from being injected with Joker Venom - a poison which kills, leaving a smile on the victim's face.
Joker escapes, but only temporarily as Batman tracks him down once again. This time the Dynamic Duo is able to take down the villain and send him to prison.