Con Air, Last Action Hero, Brainscan and Die Hard 4.0 could all have been very different films, going by the early drafts of their scripts.

The life of a Hollywood screenwriter might sound like a glamorous one, but it's not all premieres and champagne.

As one of the smaller cogs in an often complex machine, the writer can often find his or her work changed almost beyond recognition by other hands. Such is the case with the following movies, which were all changed quite drastically in one way or another between their original draft and their final cut.

Some scripts were pressed into service as sequels. Some began in one genre and wound up in another. Rather than put together an exhaustive list, we've chosen a few examples of the script changes that intrigued or bemused us most.

Con Air

Nic Cage with lank hair and a thick southern drawl. An...