Movie Scenes Actors Couldn't Get Through Without Laughing

Movie sets are arguably the weirdest workplaces on the planet, rife for screw-ups and joking around. Gag reels have led us to believe it's usually during (bad) comedies that the best messing occurs, but what about when actors get the giggles so badly—and organically—that their scenes make it into the finished product?

Here are some of the best examples of actors breaking down when they were supposed to be taking things much more seriously.

The late Oscar-winner Philip Seymour Hoffman. Multiple-time Oscar nominees Joaquin Phoenix and Amy Adams. Emmy-winning Mr. Robot star Rami Malek. They're all here in an elevator filming a scene for Paul Thomas Anderson's pensive, thought-provoking The Master. But then somebody goes and does the one thing nobody is ever supposed to do in an elevator: let one rip. All those very serious actors can't help but laugh, because farts are always hilarious.

Ewan McGregor was arguably the best thing about the Star Wars prequels (alongside fellow actual thespians Sam Jackson and Liam Neeson). This esteemed actor somehow sold the shoddy material, but he couldn't quite sell every line, noticeably hiding a smile behind his hand immediately after delivering the laughable reference to "killing younglings."

Ever the professional, Steve Carell opted for a real-life chest waxing for a scene in The 40-Year-Old Virgin. Somehow, he didn't realize how painful it would be. His natural reactions made it into the film and his fellow actors, clearly shocked, aren't quite sure how to respond to his screams of pain. (In the end, they laugh. A lot.)

Capturing a climactic, life-or-death situation has got to be one of the hardest scenes to shoot, so it's only natural that the actors can sometimes get a little overwhelmed and punchy—which seems to have been the case while filming this tense scene in 2009's Star Trek reboot. Stoic, stone-faced Spock, played by Zachary Quinto, has some big questions for Scotty, played by Simon Pegg, but he can't make himself stop laughing long enough to ask them. And Pegg's improvised quips certainly don't help him get back into character.

Apart from his roles in Marvel Cinematic Universe movies as archer extraordinaire Hawkeye, Jeremy Renner has starred primarily in hard-hitting dramas such as The Hurt Locker and The Town. He doesn't usually play funny guys, so it comes off as a little crazed and alarming in The Avengers: Age of Ultron when he sadly approaches the body of the fallen Quicksilver and jokingly smothers him, apparently to finish the job. Quicksilver actor Aaron Taylor-Johnson plays along, squirming and flailing.

Marvel acquired some legitimate acting talent when the studio landed the esteemed Benedict Cumberbatch to lead Doctor Strange. Best known for playing complicated characters like World War II codebreaker Alan Turning in The Imitation Game and Sherlock Holmes on Sherlock, Cumberbatch seems like he'd be a pretty serious guy. But maybe that's because he'd never had to film a fight sequence with some sweet martial arts moves. It's all just a bit too silly for Cumberbatch to take, and he winds up turning the whole thing into a funky-fresh dance routine.

Somehow the line "My wife used to fart when she was nervous" is even funnier coming out of the mouth of a deadpan Robin Williams. As therapist to reluctant patient Matt Damon in Good Will Hunting, Williams provokes a fit of wonderfully genuine laughter from his young co-star. Once Damon lets go, that's it. He's gone. And his real laugh sounds weird enough that we know Damon isn't faking it, which somehow makes the moment even more charming.

Although it's easily the best offering in a series that got steadily worse with each installment, American Pie isn't as notable for its gross-out humor as one might imagine. That is, save for one ludicrously effective scene featuring poor Finch (Eddie Kaye Thomas), who suffers thanks to arch-enemy Stifler slipping laxatives into his coffee, leaving him to relieve himself in the ladies' room. Thomas goes full force with the scene, but lets out a tiny grin towards the end to let us know he's in on the joke. Blink and you'll miss it.

One of the funniest moments in Kubrick's brilliant 1964 Cold War satire Dr. Strangelove or: How I Learned to Stop Worrying and Love the Bomb finds the titular former Nazi scientist (played by the incomparable Peter Sellers) struggling to control his own arm. Although Sellers, er, sells it to the best of his ability, Peter Bull (standing to his left in the shot) can't quite keep it together in the face of such blatant hilarity. And, really, who could blame him?

The infamous lineup sequence in The Usual Suspects was actually meant to be a far more serious affair. Unfortunately, Stephen Baldwin and Benicio Del Toro (who was, allegedly, annoyed he didn't have a bigger role in the movie) wouldn't play ball. After attempting for to get it right, over the course of an entire day's filming, director Bryan Singer instead decided to use the funniest takes. And the flick is all the better for it.