Eric Stoltz’s time playing Marty McFly was cut short before Michael J. Fox stepped in, partially due to his interpretation of Back to the Future’s ending as a tragedy. Back to the Future's ending is bleak and the movie ends with Marty McFly returning back to 1985 from his trip to 1955. Along the way, Marty actually adjusted his own future, returning to a version of 1985 where his family members were now better versions of themselves, changing the entire dynamic he had always known.
Before Michael J. Fox was cast in the iconic role of Marty McFly, Eric Stoltz began the movie’s production as the character. Stoltz was fired from Back to the Future and eventually replaced by Fox after the creators decided to go another route with Marty’s character approach as well as changes to the content. One of the reasons Stoltz was let go was because of the intense way he interpreted and portrayed Marty, which wasn’t how the movie's writers intended the story to be played, despite the fact that Back to the Future's ending is depressing.
Related: Will Eric Stoltz's Back To The Future Footage Ever Be Released?
In an interview for Netflix’s The Movies That Made Us, the Back to the Future creators gave an interview about Stoltz's time as Marty McFly, where they discussed how his depressing reading of Back to the Future’s ending was part of what lost him the role. Stoltz’s interpretation was that Back to the Future was a tragedy since Marty returns to the future with an entirely new life, making him an outsider in his family. The reading may have gotten Stoltz fired, but he has a point.
Marty is essentially a stranger to his own life when he returns home; he knows that his family isn’t who they were before, and while he can put the pieces
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