Great Sci-Fi Movie Scenes That Were Improvised By Actors

Movie fans love to discover behind-the-scenes tidbits about their favorite films, and there are few movie facts more exciting than an improvised line or scene. Stories of improvisation remind us that filmmaking is a collaborative, creative process, and that sometimes the most unexpected ideas make the biggest impact.

Writers and directors lay the foundation and set the scene, while it's up to actors to make the characters their own. Take one of the most classic lines in "The Godfather," a perfect example of improvisation upon a strong foundation. The phrase "leave the gun," was written in the script, but actor Richard Castellano added the line "take the cannoli," turning it into the iconic catchphrase it is today. Clearly, Francis Ford Coppola's decision to keep that ad-lib in the final cut was the right one.

We now turn our attention to the world of science fiction, where actors are often tasked with reacting to things that they can't see and don't exist in the real world. This suspension of disbelief can lead to some pretty hilarious moments, and in the right context, some powerful ones too. If you're a fan of science fiction, you'll likely recognize many of these famous scenes, but did you know they were all improvised by the actors? There's a reason they call it movie magic.

When we think of the greatest monologues in movie history, we tend to imagine a brilliant writer sitting down to pen a weighty piece of dialogue. Think of Paul Thomas Anderson cooking up the showstopping milkshake monologue in "There Will Be Blood." But when you look at how movies really get made, that's not always the case. For example, let's consider the 1982 film "Blade Runner," Ridley Scott's science fiction masterpiece. The most memorable scene in the film is the "tears in the rain" monologue, which serves as Roy Batty's (Rutger Hauer) profound final line of dialogue before his demise. The monologue reads:

"I've seen things, you people wouldn't believe. Attack ships on fire off the shoulder of Orion. I've watched C-beams glitter in the dark near the Tannhauser Gate. All those moments will be lost in time like tears in rain. Time to die."

Hampton Fancher and David Peoples wrote the script for "Blade Runner," including Batty's monologue, but Hauer wasn't satisfied with the final product. In a MasterClass video, Hauer revealed that he "cut about 200 words out of the monologue" because Batty was dying and didn't have time for a long speech. Hauer then came up with the final "tears in the rain" line, which is now the most-quoted part of the scene. It wasn't an on-the-spot improvisation, but rather a thought that came to him at four in the morning. As he told Radio Times, Hauer didn't re-write the entire monologue — he kept in the "attack ships on fire" and "C-beams glitter" portions — but it goes to show you that sometimes, the actor does know best.

Harrison Ford, one of Hollywood's most beloved grumps, is the kind of actor who gets straight to the point. He improvised a classic "Raiders of the Lost Ark" moment in order to save time (and the well-being of his cast and crew), and that's not the only time Ford's been the architect behind a celebrated movie scene. Princess Leia (Carrie Fisher) and Han Solo (Ford) may be an iconic movie couple, but they don't exactly have a picture-perfect romance. Their final scene together in the film perfectly encapsulates their complicated dynamic. Leia tells Han "I love you," and he responds, in typical Han fashion, "I know."

That last line wasn't in the script, which originally had Han respond, "I love you, too." Director Irvin Kershner wasn't satisfied with the dialogue, so he and Ford hashed out a better response. "If she says, 'I love you,' and I say, 'I know,' it's beautiful and it's acceptable and it's funny," Ford said (via Yahoo! News). It wasn't an easy day on set, and shooting the scene caused frustration and fainting because of how hot it was.

Then there was the problem of convincing George Lucas, who was initially not a fan of the line, to keep it in the movie. He worried the audience would laugh during this very sincere moment, which of course they did during test screenings. But, as Kershner told StarWars.com, he eventually came around and agreed that it cuts the tension in a way that benefits the film's momentum.

As a rapper and actor who got his start on a snappy sitcom, it's no surprise Will Smith is well-versed in the art of improvisation. "Independence Day," Smith's first foray into blockbuster territory, gave him a chance to flex that muscle. According to director Dean Devlin (via Republic World), plenty of dialogue was improvised, including most of the scenes between Smith, Jeff Goldblum, and Judd Hirsch.

One hilarious "Independence Day" line stands out for being particularly quirky, and it was all Smith. The scene in question depicts Smith's character dragging the body of an alien across the Utah salt flats. Out of nowhere, he exclaims, "And what the hell is that smell?!" As WhatCulture reports, Smith did in fact smell something awful that day. Millions of brine shrimp reside in the salt flats, and when they die, they decompose in the mud and produce a terrible odor.

The internet backs up Smith's reaction to the unique landscape. On a Reddit board discussing the scene, one Redditor wrote "It's truly the worst thing I've ever smelled. I thought it was some crazy sewage dump at first." Don't count out the natural world when it comes to improvising an amusing scene.

Considering how tightly locked in the scripts are, a Marvel movie might not seem like the ideal place to improvise. But, as Robert Downey Jr. can tell you, it's not impossible. Downey Jr. is best known for his portrayal of Tony Stark, which he originated in the 2008 film "Iron Man." That film happens to be the first film in the MCU, part of an early group of films known as "Phase One." While Marvel boss Kevin Feige is famous for running a tight ship, he loved Downey Jr.'s canon-defying line so much that he kept it in the film.

At the end of the movie, Stark reads out a pre-written speech but goes off-book and tells the world, "I am Iron Man," which he doesn't do in the comics. "That seems very much in keeping with who that character is," Feige told Deadline about their decision to include the line. That one improvisation affected how the studio did business from then on. "I think it did inspire us on all the movies," Feige explained. "They expect us to be inspired by the comics as opposed to being slavishly devoted to them."

"I am Iron Man" became Tony Stark's catchphrase, and it's also his final line in "Endgame" before he sacrifices himself for the greater good. We all have Robert Downey Jr. to thank for shaking things up for the better.

Spider-Man has long been one of the most lovable characters in the MCU, and Tom Holland's take on the character further cements that status. It makes sense, then, that the most tear-jerking moment in "Avengers: Infinity War" involves our favorite webhead. In case you've forgotten, the film revolves around Thanos' (Josh Brolin) plot to erase half of the universe's population with a literal snap of his figures. The erased half return from non-existence in "Endgame," but that doesn't make their initial disappearance any less painful.

Case in point: Spider-Man's slow, painful dissolution into nothing. Thanks to his Spidey sense, Peter is the only Avenger who knows he's going to turn to dust just before it happens, and this realization hits him like a ton of bricks. He holds tight to his mentor, Tony Stark (Robert Downey Jr.), while tearfully repeating the line "I don't want to go."

And wouldn't you know it — that fateful line was totally unscripted. Holland told GQ that his technique for making himself cry is to repeat a phrase in his head over and over again in order to bring up strong emotions. In a romantic scene, that phrase might be something like, "I love you," but in this case, he wanted to emphasize Peter's fear of death. He decided to repeat the phrase, "I don't want to go," out loud instead of in his head, and the scene came together beautifully.

There's nothing more satisfying than a good action movie one-liner. From "I'll be back" in "The Terminator" to "Say hello to my little friend" in "Scarface," these zingers stand the test of time because of their goofy theatricality. We tend to associate these lines more with the actors who said them than the writers or directors of the films, and in the case of John Carpenter's "They Live," that association is justified. In fact, the film's star, WWE wrestler Roddy Piper, deserves all the credit for the movie's most famous line.

If you're a fan of the film, you probably know which line we're referring to. Piper's character, referred to as John Nada in the script, walks into a bank holding a shotgun and encounters a horde of aliens. (He can tell they're aliens because of his special sunglasses.) "I have come here to chew bubblegum and kick ass," he says. "And I'm all out of bubblegum."

It's an extremely silly line, but it works because Piper's the one delivering it. As a former WWE star, he knew all about putting on a show. But what does the line even mean? Piper wasn't sure himself. "Yeah, I couldn't tell you what it really means, either," he said in an interview. "It was one of those — 'Roddy, you've got bullets on you, you've got a shotgun, you've got sunglasses, you go into a bank, you're not gonna rob it, say something ... action!'" And the rest was history.

The original "Ghostbusters" movie, starring comedy legend Bill Murray, is one of many instances where the actor proves his funnyman chops. The film was so big Murray felt "radioactive" afterward and left the country, and his uproarious improv is a huge reason for its success. So which lines did Murray improvise in the film? Well, most of them. Jason Reitman, whose father directed the movie, told Entertainment Weekly, "While almost all of the dialogue in the original screenplay is echoed on screen, the Venkman character is completely improvised. It's as if Bill Murray was given a mumblecore-style essay about each scene and then permitted to say whatever he wanted as long as he got the point across."

For example, while the line, "He slimed me" is in the script, the following line, "I feel so funky," was not. Venkman's tablecloth-removing magician act was also a total improvisation. Murray, along with writers Dan Aykroyd and Harold Ramis, are even responsible for creating new English slang. In the screenplay, Aykroyd and Ramis wrote the line, "That's it! I'm gonna turn this guy into toast!" On the day of shooting, Murray changed it to, "This chick is toast," and it stuck. As far as we can tell, Murray's quip is the origin of the phrase "such and such is toast" to mean something is dead or over. Not bad for a supernatural comedy involving green slime.

One of the greatest movie sequels of all time, "Aliens" masterfully combines horror, action, and the occasional burst of humor to create something truly special. Best remembered for Sigourney Weaver's badass performance and her maternal relationship with the young Newt (Carrie Hen), James Cameron's ode to motherhood also features the late and great Bill Paxton, who plays Hudson, an essential role in the film. During a panel appearance, Cameron discussed the importance of Hudson, who makes the audience laugh and releases some of the tension.

Paxton told Uproxx how he came up with the line, noting that he's not great at "improvising on the spot" but that Cameron's has a great memory, adding, "He'd remember something I'd said when we were rehearsing at a scene we were shooting two months later." Paxton's famous "game over" moment was one such line that Cameron latched on to and decided to keep in the film.

Reflecting on his character's background, Paxton shared, "He probably came up on video games and back in those days you always ... I don't think they do it anymore because I don't play video games, but it always, at the end of your quarter, [it said] 'Game over.'...'Wow, has anybody ever used that, I wonder? Because it's good.' I had no idea it would catch on." And catch on, it did.

When Paul Verhoeven first read the script for "Robocop," he threw it in the trash can. It was his wife that convinced him there was something worth exploring, and thank God she did. A critique of Reaganomics and corporate greed, the film is also a hilarious action flick with plenty of good zingers. Edward Neumeier and Michael Miner wrote the script that Verhoeven eventually fished out of the trash, and the actors did their part to elevate the material.

Kurtwood Smith, who plays the slimy crime lord Clarence Boddicker, improvised many of his character's memorable moments. For example, when he's about to throw a man who crossed him out the window, he asks, "Can you fly, Bobby?" In "RoboDoc: The Creation of RoboCop," Smith reflected on coming up with the line. "Ed [Neumeier] and I worked on scenes pretty much on the set. I was always looking for, kind of hipper ways to say things," he explained.

"This guy screwed this whole thing up. And so I wanna say something nasty," Smith recalls. "I thought well, you know, I'm gonna throw him out, let's see if he flies." It's a great quip, and it's one of many Smith worked on with Neumeier. Smith even got the chance to improvise alongside his wife, Joan Pirkle, who plays a secretary in the film. "I've got some free time. Maybe you could uh... fit me in?" he asks her. Kudos to her for not shuddering in the face of her sleazy husband.

When you think of the most iconic moments in Steven Spielberg's beloved "Jurassic Park," your mind likely goes to Laura Dern's "Woman inherits the Earth speech" or that time Jeff Goldblum inexplicably bears his chest. You might be wondering how and why that scene came to be, and so are we. While Goldblum has tried to explain how it happened, he's still not quite sure. What we do know is that his sexy pose was improvised.

As he told Vanity Fair, the moment "had nothing to do with my character. It had nothing to do with the movie. I don't know; it just happened." As a guest on "The Tonight Show Starring Jimmy Fallon." Goldblum tried to justify the spicy moment. His best guess is that it had something to do with his injured leg, which is why he's lying down the way he is. That doesn't explain why his shirt had to be unbuttoned like that, but we're not about to complain. Sometimes these things just happen, and there's no use trying to find a rhyme or reason.