Deadpool was first in development in 2004, when David S. Goyer was working on the screenplay. Goyer then declared on a message board that he’d decided to move-on to other projects. On 5th January 2010, progress had been made toward a Deadpool feature, with Variety reporting that Rhett Reese and Paul Wernick had been hired. Resse and Wernick were reportedly enthusiastic to be accurate to the Deadpool character.
On 22nd July 2010, Music Television reported from San Diego Comic Con International that director Robert Rodriguez had been sent a copy:
They sent me a script to read, I’ve been really swamped with this other stuff. So whether or not I would help develop or not is the question right now. It was really good. It wasn’t supposed to be sent out, it was one of those early drafts. I got an early sneak peek at it.
In further drafts, the characters Cannonball and Garrison Kane were omitted – Garrison Kane for the high-budget requirements of his metal arms, and Cannonball over worries that he’d be an unpopular character. Wyre was due to appear as an antagonist, but was also removed. Cable was initially considered to be included, but was decided to work better in a future film. At least one draft of the screenplay was leaked on Slide Share, and is now available to view.