12 Major Hollywood Movies That Began Filming While They Were Still Writing The Script

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Vote up the most entertaining stories about filmmakers that wrote their scripts on the fly.

Most movie fans are aware that films routinely go through multiple rounds of rewrites before they enter production. In some cases, studios and producers can bring in dozens of writers for new takes on a concept, some of whom are credited, some of whom are not. However, movie productions do have a finite amount of time, and it's also common for films to enter production without a completed script.

In more recent years, especially during the era of the blockbuster film and the rise of sequels, the demand for more movies has created shorter timelines. That means movies like Pirates of the Caribbean: Dead Man's Chest get far less time in the screenplay phase than Pirates of the Caribbean: Curse of the Black Pearl did. 

However, the idea of movies beginning production without a fully completed script isn't new, either. For decades, directors have had to go to set without finished scripts. In some cases, this dooms the production, leading to reshoots or even completely changed endings. But sometimes these movies turn out to be huge hits anyway. 

Here are 12 movies that began filming while they were still writing the script.