Marsha, the Queen of Diamonds, is after the giant diamond that powers the Batcomputer. With her love darts, she puts both Commissioner Gordon and Chief O'Hara under her spell (and into her custody). When the Dynamic Duo show up, they too are injected with her love potion, and Batman must agree to marry Marsha if he ever wants his friends to be returned.

Hoping to obtain the Batcave's bat-diamond, Marsha searches for a new potion to use on the Caped Crusaders. Batman and Robin do some searching of their own and arrive at the criminal's hideout. But after Marsha douses them with her concoctions, the villainess seems to have a unique bargaining chip - two tiny caped toads - with which to gain Commissioner Gordon's help in locating the Batcave.