Despite his reputation as a buffoon and funny book character, Plastic Man is actually one of DC’s most powerful heroes. Not only can 'Plas' reshape his body into anything and everything he can imagine, but his flexible form is virtually indestructible. He's also immortal, as he once got sent back into the distant past and lived for billions of years before arriving back in the present.
But despite all this, Batman still came up with a tactic to beat the JLA’s most invulnerable member. Even better, Batman’s genius tactic to defeat Plastic Man was so effective, it was later used by a Marvel villain, too. Yes, bizarre as it may seem, the one and only Doctor Doom used Batman’s strategies against his own stretchable nemesis Reed Richards, leader of the Fantastic Four!
Back in 2000, DC ran a four-issue storyline in the main JLA series entitled “Tower of Babel.” The story had Batman’s nemesis Ra’s al Ghul steal plans Bruce Wayne had developed to neutralize every member of the Justice League (but only in the event that any or all of them became a threat to humanity). While Batman never turned on his teammates, Ra’s adapted them to his own needs and began taking out the League members one by one. In the case of Plastic Man, Batman’s strategy was deceptively simple: spray him with liquid nitrogen. The chemical turned Plastic Man’s normally flexible form so brittle, none of his usual stretchable moves could work. Worse, one wrong move... and Plastic Man would shatter into a million pieces.
Fortunately, Plastic Man managed to pull himself back together and even assist some of the other League members against Batman’s death traps. However, the experience left Eel O’Brian badly shaken and he took on a more serious, even cynical persona for a time. When the JLA voted whether or not to let Batman stay on the team, Plastic Man actually voted against Bruce Wayne despite their earlier friendship. Given how Ra’s had invaded his private files, Batman likely went to great lengths to increase his security and prevent other villains from gaining access to his plans – but apparently his security didn’t shield him from evil geniuses who resided in different universes.
In 2005, the first theatrically released Fantastic Four movie was released. During the film’s climactic battle, Doctor Doom (Julian McMahon) captures Mr. Fantastic (Ioan Gruffudd) and decides to… pump him full of liquid nitrogen to prevent him from using his stretchable powers to escape. Reed’s teammates would rescue him, but Doom’s strategy bore a strange resemblance to Batman’s own plan to neutralize Plastic Man.
Granted, Reed’s stretchable powers were not as extreme as Plastic Man’s, but Doctor Doom’s “cold treatment” was remarkably effective. Perhaps Batman should invest in multiverse-level security?