There's so many iconic movie moments that we have to thank script-writers for.
Moments that we can recite to our friends, use the pictures on social media, and just relive as happy memories.
Often times, it's due to genius script-writing and a team of creative experts that bring us these moments. But there are moments, and yes they are rare, the actors themselves improvise on set and end up making the movie even more special.
Check out some of most iconic movie moments that were actually improvised on set! Some of them may surprise you.
1. Willy Wonka And The Chocolate Factory, Wonka's entrance
Gene Wilder only accepted the role on the condition that he got to add this entrance. He believed, "From that time on, no one will know if I'm lying or telling the truth."
2. Dumb and Dumber, The Most Annoying Sound In the World
The hitchhiking scene is totally improvised. One of the directors actually said that about 15% of the film was totally improvised.
3. Pretty Woman, The Jewellery Box Close
Julia Roberts' reaction was totally genuine. Richard Gere's snap of the box wasn't planned according to director, Garry Marshall.
4. The Lord of the Rings: The Fellowship of the Ring, Aragorn screaming
Viggo Mortensen is supposed to kick a helmet out of frustration during the scene, but he ended up breaking his toe when he did. The scream you hear is is very, very real.
5. Harry Potter and the Chamber Of Secrets, Rubber Duck Scene
According to one of the Weasley brothers in the scene, Mark Williams would change the line in each take they did. And every single time it was hilarious.
6. Clueless, "Keepin' it real."
Donald Faison says he heard the term from a neighbor and just figured that's what the kids are saying now.
7. Fast & Furious 6, "Big-ass forehead"
"We do a lot of different takes and a lot of our ideas make it into the movie," said Ludacris. "At the end of Fast Six when I spit out my drink and laugh at The Rock's comments to Tyrese, I'd whispered to him to joke on Tyrese."
8. Jaws, You're gonna need a bigger boat.
The actor just happened to say this as a joke when he saw the giant shark's appearance. It's now one of the most favorite lines in movie history.
9. Zoolander, Why Male Models?
Turns out, Ben Stiller forgot what his actual line was supposed to be after David Duchovny's speech, so he decided to wing it.
10. Midnight Cowboy, I'm walking here.
This was a real reaction from Dustin Hoffman as a cab almost hit them during filming. "So I said, 'I'm walking here,' meaning, 'We're shooting a scene here, and this is the first time we ever got it right, and you have f****d us up," says Hoffman.
11. Ghostbusters, The Party Scene
According to the director, Rick Moranis brought all his own idea to the scene and made things up as he went along.
12. Bridesmaids, The Pooping Scene
This wasn't part of the original script, but just the genius of a hilarious cast.
13. The Shining, Here's Johnny
Jack Nicholson admitted to borrowing the line from The Tonight Show Starring Johnny Carson.
14. The Dark Knight, Slow Clapping
The unsettling and darkly brilliant moment was improvised by the late Heath Ledger. He never changes his facial expression, which makes it even more terrifying.
15. Good Will Hunting, Farting Wife
This scene was totally improvised by Robin Williams. You can see the genuine laughter from Matt Damon, and you can even see the camera shake a little from laughter. This movie earned Robin Williams an Academy Award for his dramatic performance, but he was still sure to plug his comedic skills.