The endings to these famous films are very well-established, but the end product could have been very different. These actual alternate endings were written and, in some cases, filmed before being derailed for one reason or another. Imagine how different these flicks could have been.
I Am Legend
The original ending was closer to the book’s ending – the realization that Will Smith’s character is actually the villain. He’s been killing off these creatures for the whole film, which you find out are actually civilized and caring beings just trying to protect their own. Whoops.