Sometimes the best moments in life are those which are unplanned or unexpected and it seems this is also true in the movies. As it happens some of favorite movie scenes didn't exactly turn out as they were scripted, instead the actors had a moment of inspiration on set leading to some memorable movie magic. Here’s 10 of our favourite unscripted and improvised screen moments.

GoodfellasRay Liotta, Robert DeNiro and Joe Pesci in Goodfellas

Goodfellas

Joe Pesci and Ray Liotta were given free reign by Scorsese in their famous restaurant scene. Pesci based the entire exchange on a real life encounter he had with a gangster, where he made the mistake of telling him he was funny. All the dialogue was improvised and none of the other actors knew what was going to happen, making their reactions extra authentic.

The Shining

There’s no doubt that axe wielding Jack Nicholson chopping through a bathroom door in The Shinning is one of cinema’s most iconic scenes. But would it be so well remembered if it wasn't for Nicholson exclaiming Ed McMahon’s famous ‘Tonight Show’ catchphrase, “Here’s Johnny”? Maybe not, but rather than this being part of Kubrick’s original script, this line was actually an improvisation by Nicholson.

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The Dark Knight

Sometimes the most simple touches to a character are the most effective, as Heath Ledger proved more than once during his performance as the Joker. Once such moment, which was entirely improvised on Ledger’s part, was the infamous slow clap delivered from his jail cell. The improv was perfect for the character, creepy and very unsettling.

Zoolander

"Why male models?”, asks Ben Stiller’s Derek Zoolander, when David Duchovny is explaining the role of the fashion industry in political assignations. The question was so potent that even after Duchovny delivered the answer, Stiller asked again. The real reason behind Stiller’s repeat question was simply that he had forgotten his next line so he decided to repeat his last one. Duchovny ad-libbed with "Are you kidding? I just told you like a minute ago.” making one of the movie’s funniest exchanges.

Indiana JonesIndy's Raiders of the Lost Ark fight once looked very different

Indiana Jones: Raiders of the Lost Ark

It turns out that the one thing Indiana Jones can’t defeat is food poisoning. Ok this one might be more Harrison than Indy but it led to a last minute script change that created an iconic scene. Originally when Indy ran into the swordsman dressed in black the two were meant to have a long fight. But when Ford found himself struck down with a bout of food poisoning, he wasn't feeling up to too much action and the scene was changed. Thus Indy and his revolver made short work of the sword wielding villain.

Next: Jaws, Mars Attacks and The Empire Strikes Back go unscripted