Eric Stoltz was famously dropped from the sci-fi classic Back To The Future several weeks into production, but some cast members believe he is still in the movie. Michael J. Fox was always Robert Zemeckis' first choice to play the time-traveling teen Marty McFly, but scheduling conflicts with Family Ties meant that the director had to look for someone else. The likes of John Cusack and Ben Stiller were considered for the Back To The Future role, but Eric Stoltz was eventually cast as Marty McFly.

Unfortunately, Eric Stoltz didn't last long on Back To The Future set. Stoltz and Zemeckis clashed regarding the movie's tone, with Stoltz wanting a more serious take on the script, which Zemeckis intended to be a fun, action-comedy. Over a month into shooting Back To The Future, Michael J. Fox was brought in to replace Eric Stoltz having agreed to work around his Family Ties schedule to shoot the movie in the evenings and on the weekend. Although Stoltz's scenes were reshot with Fox, some believe that the original Marty McFly still appears in Back To The Future.

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According to Biff Tannen actor Thomas F. Wilson, Eric Stoltz briefly appears in Back To The Future. During the scene where Marty punches Biff in Lou's Cafe, the actor who throws the punch is way too tall to be Michael J. Fox. Wilson claims that he doesn't remember filming that scene when Back To The Future was being reshot with Fox, so it must have been leftover footage from Stoltz's time on set.

Why Eric Stoltz Probably Isn't Still In Back To The Future

Despite Wilson's claims, however, an interview for Netflix's The Movie's That Made Us with Back To The Future editor Harry Keramidas seemed to rule out the theory. Keramadis revealed that he had checked the production notes to confirm that the scene was reshot to feature Michael J. Fox, so the fired Eric Stoltz's Back To The Future footage would not have been used. But there is still some mystery around who the puncher is given their face isn't shown, and they are too tall to be Fox. The most likely explanation is that a stunt double throws the punch, but no one on the production crew has been able to confirm for sure.

Eric Stoltz filmed over a month's worth of Back To The Future footage, but the tape has not yet been released publicly. Among the scenes that Stoltz acted out is the iconic skateboarding chase scene around Courthouse Square and the first time-travel experiment with Christopher Lloyd's Emmett "Doc" Brown. With demand for unreleased versions of movies becoming more popular, like Zack Snyder's Justice League, there is a chance that Stoltz's footage could become available. But there is little doubt that Michael J. Fox's perfect performance as Marty McFly justified Eric Stoltz being replaced as Back To The Future remains one of the most loved and successful movie franchises of all time.