Having already staked a claim on the Fourth of July weekend, production on Back to the Future began in 1984 with Eric Stoltz and Christopher Lloyd in the lead roles.
When Stoltz’s tenure as Marty McFly is mentioned, it is often inferred that he might have only been in a few scenes before he was replaced. Stoltz, however, had already filmed most of Marty’s scenes.
In fact, Back to the Future had been filming for a month before Robert Zemeckis decided to make the tough call and convince Universal and Spielberg that they needed to replace Stoltz.
While Universal was onboard with the change, they were only willing to throw away a month’s worth of film if Zemeckis and Spielberg could get Michael J. Fox. Armed with a sizable check and willing to work around Fox’s Family Ties schedule, Universal was able to convince NBC and Family Ties producer Gary David Goldberg to let them use Michael J. Fox.
Aside from the obvious problems this change caused, Eric Stoltz had ingratiated himself with the rest of the cast. He socialized in the same circles as co-stars Lea Thompson, Thomas F. Wilson and Crispin Glover. Not only was Michael J. Fox an interloper, the cast was going to have to do major reshoots in the dead of night to accommodate his schedule. The producers gracefully handled the situation, however, stating that the issue wasn’t that Eric wasn’t good in the role, but that he wasn’t right for it. This caused the cast to rally around each other, despite the catastrophic turn of events.
With the film overbudget, delayed and its star replaced, Hollywood was beginning to talk about how Universal’s big budget blockbuster for 1985 was shaping up to be a bust. Only a miracle (or a passionate director) could save this shrinking ship. Time was ticking away.