Billy Crystal's ad-libs were so funny the film nearly shut down

Rob Reiner made a decision on the set of "The Princess Bride" that would cost the production nearly 30 hours of shooting time to capture five minutes of usable footage. He told Billy Crystal to forget the script. "Forget the lines, just go for it," according to actor Cary Elwes. What followed was a masterclass in why sometimes the best moments in filmmaking happen when you let the right person loose.

Crystal was playing Miracle Max, a cranky apothecary who bickers with his wife (Carol Kane) and resurrects the mostly-dead Westley with a magic pill. There were lines written. Crystal didn't use them. Instead, he improvised for hours—riffing on Yiddish inflections, inventing dialogue on the fly, never repeating himself once. The result was so funny that the set became functionally unusable.

When Laughter Breaks a Film

The sound department started removing people from set. They were ruining takes by laughing. Reiner himself, known for a loud, boisterous laugh, was among the first to be banished. He couldn't hold it together. Mandy Patinkin, who played Inigo Montoya and couldn't leave, sustained a bruised rib from trying to suppress laughter—the only injury he suffered during the entire shoot. Others bit their hands. Reiner nearly threw up. Elwes, who was supposed to lie perfectly still and hold his breath in the scene, eventually had to be replaced with a rubber dummy for most of the shoot because Crystal's performance was simply too hilarious to survive.

The scene became one of the most expensive in the film, not because of special effects or set design, but because of sheer volume of wasted footage. Elwes later wrote that the vast majority of what was filmed never made it to screen. "Unfortunately, there's so many spoiled—brilliantly hilarious takes that we all spoiled," he said.

What did survive became iconic. "Sonny, true love is the greatest thing in the world—except for a nice MLT—mutton, lettuce and tomato sandwich, where the mutton is nice and lean." That line. The character's look—a mix Crystal specifically requested, inspired by Yankees manager Casey Stengel and his own grandmother. These details came from Crystal's instincts, not a script supervisor's notes.

Fans have spent decades wishing those unseen takes would surface. The appetite is real: when "The Princess Bride" returned to theaters for its 30th anniversary in 2023, people showed up. They still do. The film has become an annual ritual for many viewers, a story so beloved that even the behind-the-scenes lore—the bruised ribs, the banished crew members, the hours of wasted film—only deepens the mythology.

We may never see the raw footage of Crystal's marathon improv session. But the scene that made it into the final cut remains proof of something filmmakers rarely get right: sometimes the best magic happens when you trust the talent and let them play.