A scenario can be perfectly written and yet leave room for the unexpected. Over the decades, actors have thus modified a scene at the last moment, sometimes with the director's agreement, sometimes simply taking advantage of an incident on set. From Shining to Blade Runner, here are five improvisations that ultimately marked the history of cinema. Some of the most famous scenes in cinema were not even written that way. A line delivered on the spot, an unexpected gesture or an idea born a few seconds before filming: sometimes, actors simply followed their instincts. And when the camera continued to roll, cinema gained some of its most memorable scenes. Jack Nicholson invents one of the most famous lines in Shining. It is hard to imagine Shining without Jack Nicholson behind the door, with an axe in hand. Yet, when the actor delivers his famous line as Jack Torrance tries to enter the bathroom, these few words were not in the script. Nicholson spontaneously launches a reference to the American television show The Tonight Show, whose host Johnny Carson was traditionally introduced with a formula that became famous. "Here’s Johnny!" Stanley Kubrick decides to keep the take. The result has become one of the most iconic images of Nicholson's career and horror cinema. What is particularly interesting is that the improvisation does not come solely from a desire to make people laugh. It perfectly corresponds to the growing madness of Jack Torrance. The scene works because Nicholson transforms an already terrifying moment into something completely unpredictable. And today, this line is so closely associated with the film that it is almost impossible to imagine this scene with the dialogue originally intended. Robin Williams transforms Will Hunting into a moment of truth. There is a very simple reason why a scene in Will Hunting seems so natural: Robin Williams was improvising. In the film by Gus Van Sant, Sean Maguire talks about his missing wife with Will Hunting, played by Matt Damon. The conversation suddenly takes a much lighter direction when Robin Williams shares some very personal habits of his wife. The anecdote was not planned in the script. Robin Williams invents it during the take and causes a completely spontaneous reaction from Matt Damon. Damon's laughter is therefore partly that of the actor surprised by what his partner has just done. Even the camera betrays the moment: it slightly shakes, the cinematographer also having difficulty holding back his laughter. Robin Williams will continue to improvise regularly during the filming. Another one of his improvisations appears at the very end of the film, in a line that became famous. The most beautiful thing about this story is that the improvisation does not only give the scene a comedic touch. It allows the creation of a real complicity between the two characters. Robin Williams will win the Oscar for best supporting actor for his performance. Harrison Ford abandons the duel in Indiana Jones. This time, the improvisation was born from a very real constraint. In Raiders of the Lost Ark, Indiana Jones must face an impressive swordsman who spins his weapon in front of him. The scene was supposed to result in a real fight. But Harrison Ford was sick during the filming in Tunisia, notably due to particularly violent digestive problems. He simply did not have the energy needed to film the long sequence planned. Harrison Ford then proposes a solution to Steven Spielberg: instead of fighting the man, Indiana Jones could simply pull out his revolver and shoot him. Spielberg accepts. The scene is filmed. And it becomes one of the most famous comedic moments in the entire Indiana Jones saga. The contrast is perfect: the swordsman seems ready to deliver a spectacular fight, while Indiana Jones, clearly unimpressed, solves the problem in seconds. What could have been a simple production problem becomes a scene that perfectly defines the character: Indiana Jones is not there to respect the rules of a heroic duel, he simply wants to survive. And all of this was born because Harrison Ford was too sick to film the original scene! Roy Scheider invents a legendary phrase in Jaws. There are improvisations that change a scene. And then there are those that change the way a film is summarized by a single phrase. In Jaws, Chief Brody discovers the size of the shark and immediately understands that something much bigger will be needed to face it. The famous line was not the one originally planned. Roy Scheider improvises the wording, and Steven Spielberg decides to keep it. The result has become one of the most famous quotes in the history of blockbusters. This improvisation works mainly because it instantly summarizes the situation. The character does not need to explain what he has just seen: his reaction is enough. And the phrase has become so famous that it has largely exceeded the film's boundaries. "You're gonna need a bigger boat." It has since been regularly used to describe a situation that turns out to be much larger or more complicated than expected. A small improvisation lasting just a few seconds has therefore succeeded in becoming a cultural reference in its own right. Rutger Hauer rewrites his own destiny in Blade Runner. One of the most fascinating examples is that of Rutger Hauer in Blade Runner. His character, Roy Batty, delivers at the end of the film a monologue that has become legendary as he is about to die. But the version we know is not simply that of the original script. Rutger Hauer has largely contributed to modifying the text, notably shortening and reorganizing his speech before filming. He adds a much more poetic dimension to the scene. "All these moments will be lost in time, like tears in rain. It is time to die." Director Ridley Scott keeps this version. And the result has become one of the most famous passages in science fiction. The strength of this improvisation comes mainly from the contrast: Roy Batty is presented for much of the film as a threat. Yet, at the moment of death, his character suddenly becomes deeply melancholic. Rutger Hauer understands that the speech must resemble a last memory that disappears with him. The scene therefore completely transforms the character. Decades later, this monologue remains one of the most quoted moments in Blade Runner and one of Rutger Hauer's most memorable performances. When improvisation becomes stronger than the script. These five stories have something in common: the improvisation was not necessarily intended to become the strong moment of the film. Jack Nicholson finds an unexpected line. Robin Williams transforms a dramatic conversation into a real exchange between two actors. Harrison Ford adapts a scene because he is sick. Roy Scheider finds a formulation that will become cult. And Rutger Hauer transforms a written monologue into a true testament for his character. The most fascinating thing is that these moments never really give the impression of being improvised. It is probably the sign of good improvisation in cinema: it does not look like an error or a deviation from the script. It simply gives the impression that the character has just done exactly what he was supposed to do. And sometimes, a few seconds of freedom are enough to create a scene that viewers will continue to quote for decades.