Back in the innocent days of the 1990s, when a new superhero film wasn’t released every week or so, the sting of a comic-book movie flop was especially painful. But none was quite as excruciating as the now 20-year-old Batman and Robin, which was rather terrible despite its all-star cast of George Clooney, Alicia Silverstone, Uma Thurman, and Arnold Schwarzenegger. Its over-the-top, incredibly goofy tone and lack of self-awareness immediately destined it for camp infamy, and few things contributed to its legacy like the absurd number of groan-worthy ice puns from Schwarzenegger’s Mr. Freeze.
As it turns out, Schwarzenegger did quite a bit of suffering while delivering those infamous lines — and some of it may have actually been toxic. An oral history of the film detailed in The Hollywood Reporter explains that in order to complete the elaborate costume of Mr. Freeze, Schwarzenegger would have lights placed into his mouth, and battery acid would often leak out as a result, presenting a serious challenge:
The final touch for close-ups was an LED light for Mr. Freeze’s mouth. It made delivering lines a challenge, but even worse, it proved to be a serious danger.
“When you put it in Arnold’s mouth, Arnold’s saliva would creep into the seams of this thing and attack the batteries. The batteries would immediately start disintegrating and start putting out battery acid into Arnold’s mouth,” says [makeup artist Jeff] Dawn.
The actor was not happy, shouting, “It tastes like shit! What’s in my mouth?”
Here’s hoping that on-set safety has improved since the 1990s.