The major casting change that nearly derailed 'Back to the Future'
Quick take
- Eric Stoltz played Marty McFly for roughly five weeks, shooting major scenes before he was let go in January 1985.
- Robert Zemeckis and Bob Gale felt his performance lacked the comic energy the character needed.
- Michael J. Fox had been their first choice, but his "Family Ties" commitments kept him out of reach.
- The swap meant redoing weeks of work, shooting overnight and pushing the release from June 21 to July 3, 1985.
Few performances are welded to an actor the way Marty McFly is welded to Michael J. Fox. "Back to the Future" became the biggest movie of 1985, and Fox's skateboarding, guitar-shredding teenager became the face of it. But when Fox showed up for work in January 1985, the movie had already been shooting for weeks with someone else in the role. Eric Stoltz had spent about five weeks as Marty McFly, filming scenes with Christopher Lloyd's Doc Brown that would never be seen.
The problem wasn't talent. Stoltz was a serious, gifted actor, and director Robert Zemeckis had come to believe that seriousness was the wrong fit for a time-travel comedy. Replacing a lead mid-production is expensive on its own (and the man the filmmakers wanted was already starring in a hit NBC sitcom). Zemeckis has also said the team pulled Stoltz before Fox was locked in, a gamble that could have shut the whole movie down.
Eric Stoltz was already filming when the production changed course
Zemeckis and co-writer Bob Gale had wanted Fox from the start. He never got the offer. "Family Ties" creator Gary David Goldberg, worried about losing his star to a feature film, quietly turned the role down on Fox's behalf.
Fox described it in a 2025 People interview, recounted by TV Insider. With Fox off the table, the search narrowed to Stoltz and C. Thomas Howell. Universal president Sid Sheinberg was Stoltz's loudest champion, and according to cinematographer Neil Oseman's production history, Gale recalled Sheinberg promising that if it didn't work out, "you can recast it and start all over again."
Cameras rolled on Nov. 26, 1984. Over the next several weeks, Stoltz shot some of the movie's biggest moments. In his memoir, "In My Own Time," Lloyd lists the scenes he later had to do twice: Doc unveiling the DeLorean to Marty, Marty arriving in 1955 and convincing Doc he's from the future, and the two preparing for the lightning-storm escape.
Within a few weeks, Zemeckis had seen enough. He asked executive producer Steven Spielberg to watch a 45-minute rough cut of the footage. Every filmmaker in the room reached the same conclusion.
The filmmakers believed Marty McFly needed something different
Zemeckis and Gale wrote Marty as a reactive, slightly frantic everykid, the audience's stand-in. That kind of part runs on timing. Stoltz came at it from the other direction. Lloyd remembers a committed actor who stayed in character between takes and asked people to call him Marty, but who, as the producers saw it, "lacked a kind of comic flair and timing."
"He wasn't giving us the kind of humor that we thought the character should have," Gale told The Guardian for the film's 40th anniversary. Stoltz, he added, saw the story as a tragedy, since Marty ends up in a 1985 where much of his life has changed. Lea Thompson, who played Marty's mother, put it in acting terms. Stoltz was chasing the gritty, De Niro-style realism young actors revered in the '80s.
Zemeckis has never pinned the failure on Stoltz. "Eric is a brilliant actor. I simply miscast him and I learned a very serious lesson," he told CBC host George Stroumboulopoulos, as quoted by Syfy. He called the firing "the worst experience of my career."
The most striking part is the order of operations. "We removed Eric (Stoltz) from the movie before we had Michael (J. Fox)," Zemeckis said in a Golden Globes oral history. "We were completely prepared to shut the film down for however long it was gonna take to recast the part." The team decided Stoltz had to go without any guarantee that Fox (or anyone) would be available to replace him.
Not everyone remembers it that way. Other accounts, including Fox's, put Goldberg's change of heart earlier. Shortly before the 1984 Christmas break, Goldberg called Fox into his office, described the movie and asked if he could handle both jobs. Fox said yes. By that telling, Fox was lined up before Stoltz heard a word, and Zemeckis kept shooting with Stoltz through the holidays while the deal came together. Both versions agree on one thing: the decision to recast came before anyone knew Fox could say yes.
On Jan. 10, 1985, during a lunch break in the Twin Pines Mall parking lot, Zemeckis called Stoltz into his trailer and told him. That night, around midnight, Spielberg gathered the cast at a production van and announced that Stoltz was out and Fox was in. Stoltz's manager told Daily Variety the decision came "totally out of left field." Decades later, Fox wrote of his predecessor, "Eric was an immensely talented actor, but the creative team felt that he just wasn't the right fit for Marty McFly."
For the cast, the firing landed hard. "It was horrible. He was my friend and obviously a wonderful actor," Thompson said. "The minute someone gets fired, you're like, oh wait, this is a big business, this is serious, this is millions of dollars being spent."
Bringing in Michael J. Fox meant filming around the clock
Fox wasn't leaving "Family Ties," so he worked two jobs at once. Per Oseman's account, he woke at 9 a.m., worked on the sitcom from 10 a.m. to 6:30 p.m., then was driven to Universal to film "Back to the Future" until about 2:30 a.m. Scenes that needed daylight got pushed to weekends.
Fox later said he slept about three hours a night for three or four months. Lloyd remembers him sometimes sleeping in the vehicle that shuttled him between sets. There was no rehearsal and no table read. The cast simply went back to the beginning with Fox, redoing roughly five weeks of finished scenes.
The cost was real. Producer Neil Canton estimated the reshoots would add about $4 million to a movie the American Film Institute catalog puts at an $18 million budget. The schedule took a hit, too. Principal photography ran until April 26, 1985, and the release moved from June 21 to July 3.
The risky decision helped create a Hollywood classic
The gamble paid off on screen. Lloyd describes Fox's "natural comic vitality" and says their rapport came easily, which is the whole engine of the movie: an anxious kid and an unhinged scientist bouncing off each other. Thompson saw Fox work at his comedy the way the old masters did, drilling "the falling over, the double take, the spit take" for hours. That is what made Marty's predicament funny instead of tragic. "It was high stakes for everybody," Fox told People in 2025.
"Back to the Future" opened July 3, 1985, and was still the No. 1 movie in America in late October. It finished as the highest-grossing film of 1985 with $190.6 million that year, and its domestic total has since passed $212 million with re-releases. In 2007, the Library of Congress added it to the National Film Registry.
Stoltz kept working, and he's mostly kept quiet about it. The footage of him as Marty has never been released in full. The movie everyone remembers exists because a director decided to fire his star before he had a replacement.
