When Batman and Robin get a tip that Commodore Schmidlapp, owner of the Big Ben Distillery, is in danger aboard his yacht, they launch a rescue mission using the
Batcopter. As Batman descends on the bat-ladder to land on the yacht, it suddenly vanishes beneath him. He rises out of the sea with a shark attacking his leg. After Batman dislodges it with bat-
shark repellent, the shark explodes. Batman and Robin head back to Commissioner Gordon's office, where they deduce that the tip was a set-up by the United Underworld, a gathering of four of the most powerful villains in
Gotham City:
the Joker,
the Penguin,
the Riddler, and
the Catwoman. The four criminals equip themselves with a dehydrator that can turn humans into dust until they are rehydrated (an invention of Schmidlapp's, who is unaware that he has been kidnapped), escape in a war-surplus, pre-atomic submarine made to resemble a penguin, and recruit three pirate-themed henchmen (Bluebeard, Morgan, and Quetch). Batman and Robin learn that the yacht was really a holographic projection and return via
Batboat to a buoy concealing a projector, where they are trapped on the buoy by a magnet and targeted by torpedoes. They use a radio-detonator to destroy two of the torpedoes, and a
porpoise sacrifices itself to intercept the last one. Catwoman, disguised as Soviet journalist Kitka, helps the group kidnap Bruce Wayne and pretends to be kidnapped with him, as part of a plot to lure Batman and finish him off with another of Penguin's explosive animals (of course, unaware that Wayne is Batman's alter-ego). After Wayne fights his way out of captivity, he again disguises himself as Batman, and the Dynamic Duo returns to the United Underworld's HQ, only to find a smoking bomb. Batman is met with frustration, rushing all over the docks, unable to locate a safe place to dispose of the bomb, but finally does so in the nick of time. The Penguin disguises himself as the Commodore and schemes his way into the
Batcave along with five dehydrated henchmen. This plan fails when the henchmen unexpectedly disappear into
antimatter once struck: the Penguin mistakenly rehydrates them with toxic
heavy water used to recharge the Batcave's
atomic pile, leaving them highly unstable. Ultimately, Batman and Robin are unable to prevent the kidnapping of the dehydrated
United World Organization's Security Council, consisting of ambassadors from Japan, the U.S, the U.S.S.R., Israel, France, Spain, West Germany, the United Kingdom, and Nigeria. Giving chase in the
Batboat to retrieve them (and Miss Kitka, presumed by the duo as still captive), Robin uses a sonic charge weapon to disable The Penguin's submarine and force it to surface, where a fist fight ensues. Although Batman and Robin come out on top, Batman is heartbroken to discover that his "true love," Miss Kitka, is actually Catwoman when she loses her mask. Commodore Schmidlapp accidentally breaks the powdered Council members' vials and sneezes on them, scattering the dust. Batman sets to work, constructing an elaborate Super Molecular Dust Separator to filter the mingled dust. Robin asks him whether it might be in the world's best interests for them to alter the dust samples so that humans can no longer harm one another. In response, Batman says that they cannot do so, reminding Robin of the fate of the Penguin's henchmen and their tainted rehydration, and can only hope for people, in general, to learn to live together peacefully on their own. With the world watching, the
Security Council is re-hydrated. All members are restored alive and well, but continue to squabble amongst themselves, totally oblivious of their surroundings; however, each of them now speaks the language and displays the stereotypical mannerisms of a nation other than their own. Batman quietly expresses his sincere hope to Robin that this "strange mixing of minds" does more good than harm. The duo quietly leaves
United World Headquarters by climbing out of the window and descending on their bat-ropes. ==Cast==