Acting doesn't solely rely on reading words from a script. Sometimes what makes a scene funnier, more sentimental, and generally richer on the big screen is its unconventionality and every element of surprise that comes with it. With incredible actors like Robert Downey Jr. and Chris Hemsworth, who are clearly masters at improv, it surely hasn't been hard for the MCU to deliver plenty of solid unexpected content throughout the films.

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Filmmakers know a good scene when they see one, even if it doesn't go according to plan—this list showcases exactly that. From Tony Stark's iconic one-liner to Hayley Atwell's genuine reaction to Chris Evans' muscular body, there is a great number of surprising unscripted moments in the MCU.

I Am Iron Man

Robert Downey Jr. as Tony Stark
Image via Marvel Studios

If anyone needs further proof that Robert Downey Jr. is Tony Stark himself, the Iron Man line that shaped the MCU was entirely unscripted. Though everyone knows the actor was pretty much born for the role, what makes Downey a even more appropriate fit is his commitment to the character; throughout the films Tony appears in, a great part of his dialogue was improvised—including these four iconic words.

This eternally memorable quote turned out to be not only a huge part of Tony's identity—and let's not forget that these were also his last words—but it also marked the flourishing beginning of the superhero universe.

Try Me, Beyoncé

Stephen Strange standing still and looking serious in Doctor Strange.
Image via Walt Disney Studios Motion Pictures

We've heard Benedict Cumberbatch's Doctor Strange ask Wong (Benedict Wong), in the first Doctor Strange film, if his name was "just" Wong; like Adele, Drake, Bono, and Eminem. Another singer that fits into the category is, of course, the ridiculously talented Beyoncé. What makes the scene even funnier is that the joke was improvised.

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Now, we don't know what's better about the whole situation: Strange's dry and witty sense of humor, or Wong, who clearly has no idea who the singer is, immediately going to listen to "Single Ladies" in the following scene as a form of "research."

Hulk is Thor's Friend From Work

Chris Hemsworth as Thor
Image via Walt Disney Studios Motion Pictures

A big part of Thor: Ragnarok's dialogue was improvised by the actors. What's surprising about this one in particular is that it actually was improvised by a kid on set of the film. "We had a young kid, a Make-A-Wish kid, on set that day. In between the takes, I was talking with him, and he goes, 'You know, you should say he's a friend from work!'" Hemsworth revealed.

Apart from this incredibly fun moment, Taika Waititi's hilarious film also featured a very entertaining moment between the two godly brothers—apparently, the trick "Get Help" was also improvised.

Andrew's Peter Loves The Other Peters

Andrew Garfield as Peter Parker
Image via Marvel Studios

Fans may remember that in the latest Spider-Man movie there is an extremely sweet and heartwarming moment between the three Peter Parkers. During the final fight, before all three start swinging on each other’s webs, Andrew’s Peter stops both Tom and Tobey's Peters and tells them he loves them, making the entire movie theater melt.

The actor told Variety in an interview: "There’s a line I improvised in the movie, looking at [Maguire and Holland] and I tell them I love them. That was just me loving them." It doesn't get more wholesome than that.

Why is Gamora?

Dave Bautista as Drax
Image via Marvel Studios

Infinity War is undoubtedly a very memorable film for several reasons, but what makes it even more unforgettable is the number of funny lines, which later turned into internet memes, it features; including Drax's (Dave Bautista) totally random (in the best possible way) punchline, "Why is Gamora?"

Screenwriters Christopher Markus and Stephen McFeely revealed to Yahoo that the question wasn't originally a part of the script: “The script only said, ‘Where is Gamora?’ ‘I’ll do you even better: Who is Gamora?’ And then one day Bautista just goes, ‘I’ll do you one better: Why is Gamora?’” Markus said. “It’s like, ‘OK, you’re very good at your job.’”

Tom Holland Doesn't Want To Go

Peter Parker (Tom Holland) turns to dust in Tony Stark's (Robert Downey Jr.) arms in Avengers: Infinity War
Image via Marvel Studios

Admit it, you're still not over this scene (it's okay, we aren't either). The beloved Tom Holland delivered the performance of his life in Avengers: Infinity War, breaking viewers' hearts to pieces when Peter turned into dust thanks to Thanos's (Josh Brolin) snap. While Holland has been showcasing his great talent from a very young age, the audience couldn't help being in awe of his emotional, almost genuine acting.

The young actor revealed to GQ that repeating a phrase over and over again is a technique he uses when trying to cry: "If I was in a scene, and I was talking to someone and the undertone of the scene was that I love them, I would say in my head, 'I love you so much, I love you so much, I love you so much.'" In this one particular scene, Holland decided to say the words out loud, and it ended up working surprisingly well.

Bucky and Sam's Therapy Scene

Anthony Mackie as Sam Wilson and Sebastian Stan as Bucky Barnes
Image via Marvel Studios

It is no surprise to anyone that Bucky (Sebastian Stan) and Sam (Anthony Mackie) had never been the closest of acquaintances—that is up until The Falcon and The Winter Soldier, of course. Throughout the series, viewers get to witness a beautiful friendship flourish and two very different characters develop into the best version of themselves.

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In the second episode of the Disney+ show, both characters have to face each other in an hilarious couple’s therapy-type scenario. According to Amy Aquino, who played Dr. Raynor, most of their banter during the hilarious scene wasn't scripted: "It was Anthony and Sebastian, who have this huge history. And they were doing it in character, although in between they were also having a lot of fun," the actress told ET.

Kate, Yelena and a Bowl of Macaroni

Florence Pugh as Yelena
Image via Marvel Studios

Much like Sam and Bucky at the beginning, Kate (Hailee Steinfield) and Yelena (Florence Pugh) do not share the most friendly dynamic in the Hawkeye series. Nevertheless, that didn't stop the two from sharing a bowl of instant mac 'n cheese.

Though there's great chemistry between the actresses, the tension in this scene is palpable. What makes it stand out more is the fact that most of the conversation between the characters was improvised. Director Bertie told Buzzfeed: "We did a rehearsal, but every single thing was just perfect between them, and the improvisation that they brought to it was dynamite."

Yimambe!

Chadwick Boseman as T'Challa
Image via Marvel Studios

During the unforgettable Battle of Wakanda scene in Infinity War, when Avengers join forces with the powerful Wakadan army and Jabari tribe to fight Thanos's army, the same war chant from Black Panther is chanted by Winston Duke's M'Baku, which leads all Wakandans to chant it collectively. The legendary T'Challa (Chadwick Boseman) follows up the chant with the catchphrase "Wakanda forever!" And it turns out that none of these things were a part of the script.

Contrary to what some may think, "yimambe" is a real word with an important meaning. While Wakanda is fictional, Wakanda's language is not. IsiXhosa is a Bantu language, one of the 11 official languages of South Africa. According to translators, the term means "hold off" or "hold fast".

Peggy Touches Steve's Bod

Chris Evans as Steve Rogers and Hayley Atwell as Peggy Carter
Image via Marvel Studios

If anyone has ever wondered why Hayley Atwell's Peggy Carter seemed so genuinely in awe of Chris Evans' torso during a certain scene in Captain America: The First Avenger, it was mainly because it was her first time seeing the actor without clothes on. Atwell couldn't believe her eyes, so her hands gained a life of their own.

"When Chris Evans first took his shirt off on the set of Captain America, I just instinctively grabbed his man boob. They kept it in the film. So we did a couple of takes of me being really inappropriate with my hand on his pec for the duration of the scene," the actress revealed to Esquire.

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