This is interesting.

You know how after a movie wraps up and the credits scroll, for the "Written By" section, you usually see twelve or thirteen names listed? When I was a kid and saw this, I thought to myself, "Do they all just sit in a massive room and type it out together word by word?"

No. It's just that most movie scripts go through many, many, many re-writes before they end up on screen. If the filmmakers like the story but wish the dialogue had a little more snap to it, they'll hire a new writer that's known for witty dialogue to come in and work on it. If the story may benefit from a little more adrenaline, they'll hire a new writer who has a solid history of white-knuckle thrillers. And so on, and so on.

Very rarely do I hear about scripts that avoid that adventure, and go to appear on screen without having gone through rewrite after rewrite. However, there are currently two major movies out right now that, from what I've heard, were made from scripts that were for the most part left unchanged.

Those two movies are The Social Network and Hereafter. You've more than likely heard of them.

Here's a great interview on deadline.com with Peter Morgan, the screenwriter behind Hereafter, The Last King of Scotland, The Queen, and Frost/Nixon. He talks about the events that lead up to Hereafter being made, which even involved Steven Spielberg! Enjoy:

http://www.deadline.com/2010/10/oscar-qa-peter-morgan-talks-hereafter/