Why The Flash Recast Eric Stoltz In Back To The Future & Why He Was Fired In Reality

After watching "The Flash," lots of viewers were left puzzled by unanswered questions. Why, for instance, is George Clooney there in the final scene? But one scene, in particular, has fans scratching their heads, and it has to do not with the myriad Superman and Batman cameos, but with a scene that hinges on the lead casting in the beloved family sci-fi movie "Back to the Future."

After meeting his younger self in the alternate past universe where the bulk of "The Flash" takes place, Barry (Ezra Miller) quickly realizes that this alternate timeline is fundamentally different from his own. Those differences are thrown into sharp relief when the original Barry meets alternate Barry's roommates and has a disagreement with them over who played Marty McFly in "Back to the Future." Original Barry insists that, as we all know, Michael J. Fox played the character, but alternate Barry and his roommates are sure that method actor Eric Stoltz played McFly.

That scene is one of many Easter eggs in "The Flash" referencing real-world movie trivia. In this case, it's behind-the-scenes drama from the making of "Back to the Future." As it turns out, Eric Stoltz came very close to playing the lead in Robert Zemeckis' iconic time travel movie. Not only was Stoltz originally cast as Marty McFly, but he even worked on set for a time. However, he was eventually let go from the project after it became clear that he wasn't the right fit for McFly, and Fox was hired to replace him, resulting in the movie we all know and love today.

Those familiar with his body of work might intuitively understand why Eric Stoltz didn't work as Marty McFly. The actor's credits include roles in Quentin Tarantino's "Pulp Fiction," Eric Bress' "The Butterfly Effect," and Luis Llosa's "Anaconda." He's the kind of actor's actor who takes his work with the utmost seriousness, no matter the tone of the film he's in. Stoltz is also a method actor, meaning he tries to fully embody his characters on camera and off.

Sure enough, Stoltz took a method approach to the character of Marty McFly, and things quickly got out of hand. Not only was Stoltz's technique a misplaced effort for a family action comedy, but he also reportedly took things too far, insisting that he be referred to as "Marty" while on set. At one point, Stoltz nearly came to fisticuffs with co-star Tom Wilson, who played the bully Biff Tannen, having internalized Marty's resentment of the heel character.

Ultimately, Stoltz was let go and replaced by Michael J. Fox, leading to the version of "Back to the Future" that was ultimately released. But the apartment scene in "The Flash" plays with that film's ideas about diverging timelines by digging up this little-known instance of behind-the-scenes drama from a beloved movie. If only Universal Pictures had declined to recast Stoltz, that small change would have affected film history in a big way. 

Hints of that alternate reality still exist in our own. In fact, Stoltz's IMDb still lists "Back to the Future" among his acting credits.