Classic movie scenes made up on the spot

Directors don't want actors ad-libbing all over the place. That's what scripts are there for. But sometimes, when the stars align and the timing is just right, there can be something momentous about a line thrown in, off the cuff and in the heat of the moment. Some ad-libbed lines have managed to define films, the lines that we go away from the cinema with whirling around in our heads. Here are some of the most iconic examples.

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The Shining

The filming of 'The Shining' was notoriously fraught. It's alleged that director Stanley Kubrick terrorised his timorous leading lady Shelley Duvall, and that her stress in the film is largely genuine. But in its climactic scene, where Jack Nicholson's character Jack Torrance finally snaps and picks up an axe, the line that made it all the more terrifying was ad-libbed. 'Heeeere's Johnny!' cackles Nicholson, the line used by announcer Ed McMahon to introduce Johnny Carson on The Johnny Carson Show. In a second, a bastion of wholesome American-ness was sullied forever.

Jaws

It was claimed that Robert Shaw improvised the devastating USS Indianapolis scene in 'Jaws', where he tells Hooper and Brody how he survived the sinking of a naval ship which delivered the H-Bomb in shark-infested waters. Sadly this is not the case. The story was, however, embellished by the screenwriters, who combined various stories to come up with that one. The film is not without its improvisation, however. Brody's line 'you're gonna need a bigger boat' was scripted as 'we're gonna need a bigger boat', but Roy Scheider altered it just enough to make it his.

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Full Metal Jacket

Actor R. Lee Ermey was a real life drill sergeant, having served in both Vietnam and Okinawa. He was only hired as a technical advisor for Kubrick's 'Full Metal Jacket', but after listening to a tape he made as instruction for the director, he gave Ermey the role and let him formulate and ad-lib his own dialogue, which is seen in full effect in the movie. It was rare for Kubrick to let actors work so unscripted, but he allowed it, so impressed was he with Ermey's style and authenticity.

Midnight Cowboy

It's a line that’s been aped since it was first uttered by Dustin Hoffman, though its origin remains in dispute. And quite rightly. When Hoffman's character Rizzo wanders into the road in downtown New York, a cab which had supposedly ignored the signs warning of filming in the area almost runs him over. He utters the line: “I'm walkin' here!” and then, ever the hustler, he adds 'actually that ain't a bad way to pick up insurance, y'know'. Hoffman says the line was his, ad-libbed on the spur of the moment, but producer Jerome Hellman claims it was in the script. We may never know who is telling the truth.

Taxi Driver

How irritating must it be for a screenwriter to put all that work in writing a script only for an actor to make up the lines that the world remembers? Very, one would think. And so another of the most iconic scenes of all time is another scene to have been entirely improvised. 'Raging Bull' writer Paul Schrader instructed De Niro in the script only with the direction: 'Bickle speaks to himself in the mirror.' The method actor then took it upon himself to add in his infamous 'you talkin' to me?' rant, where deluded Vietnam veteran Travis Bickle imagines how he will clean up the streets of New York.

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The Usual Suspects

The Usual Suspects was a film with a timeless quality about it, not to mention many iconic scenes. The line-up scene in particular has entered into the Hollywood canon for both its pivotal nature to the plot and for its super-cool look. It was also improvised. Stephen Baldwin, Gabriel Byrne, Benicio Del Toro, Kevin Pollack and Kevin Spacey were all given the same x-rated line to read, but no other direction. The scene is one of camaraderie, and one that would have been impossible to script and achieve the same results.

Blade Runner

Ridley Scott's epic sci-fi is steeped in movie history, with its re-edited endings and director's cuts. It remains one of the most impressive achievements of the genre, and it's rather nice to know that Rutger Hauer added his own stamp to it. As his maniac replicant Roy Batty lies dying at the end of the film, he utters lines that are said to be all his own: “I've seen things you people wouldn't believe. Attack ships on fire off the shoulder of Orion. I watched C-beams glitter in the dark near the Tannhauser gate. All those moments will be lost in time. Like tears in the rain. Time to die.” Poetry.

The Empire Strikes Back

It's sometimes only after living with a character for the length of a couple of films that you start to get a better idea of how they speak, better even than the person who has written the script. As Han Solo is about to be lowered into carbonite in 'The Empire Strikes Back', Leia declares 'I love you' to the ice-cold smuggler. Solo's scripted line was 'I love you too', which didn't seem to work. Instead George Lucas suggested Harrison Ford say what felt natural, and 'I know' came out instead. Perfect.

Can you think of any more great improvised lines? Let us know in the comments section below...