Lea Thompson Remembers Being Snooty to Michael J. Fox on Back to the Future Set

Lea Thompson says it took a while to warm to Michael J. Fox after he was hired to replace Eric Stoltz in Back to the Future.

Thompson, who starred opposite Fox in the 1985 blockbuster as time-traveling teen Marty McFly’s mother in the 1950s, joined host Steve Kmetko on the latest episode of his podcast Still Here Hollywood to discuss her career — including whether or not she hit it off with Fox on the set of Back to the Future.

“Probably not,” the actress, 63, admitted, “because I was friends with Eric Stoltz who had just gotten fired.”

Of course, nearly 40 years later, it’s hard to imagine anyone else playing Marty. But while Fox was reportedly the first choice to play the character, director Robert Zemeckis cast Stoltz when Fox was initially unavailable due to his role on NBC’s Family Ties. After filming began in November 1984, the filmmakers quickly realized they’d made a mistake and ultimately replaced Stoltz with Fox.

Thompson explained that she’d already starred opposite Stoltz in 1984’s The Wild Life, and would go on to costar with him again in 1987’s Some Kind of Wonderful. “So, he was a friend of mine,” she said.

But that wasn’t the only reason she was initially chilly toward Fox.

“I remember specifically being really snooty because there was a big division between movie stars and TV stars at that point,” Thompson said. “I remember being like, ‘He’s just a TV star, and I’m a movie star. I was in Jaws 3D.’ So, I think it took me a while to warm up to him, but he was so funny and so fun to act with.”

“I had done some scenes with Eric already and then had to redo them with Michael, so I could see how they were completely different scenes,” Thompson continued.

Somewhat counterintuitively, Thompson said that the fact that the filmmakers replaced Stoltz with Fox only made her more confident that Back to the Future would be a hit.

“When we were shooting and they replaced Eric Stoltz with Michael Fox, six weeks in, I was like, ‘Oh, they must like what they’re doing because nobody does that. That’s very expensive,’ ” she explained. “So, I had a feeling, but no one knew that it was gonna be what it was.”

But, Thompson recalled, the casting switch certainly had an impact. “You know, everybody always wants to be like, ‘Oh, wasn’t that fun?’ You know, that’s what people wanna hear,” she said. “And it was very — it was a lot of pressure, and it was scary business, especially after they fired Eric Stoltz. You were like, ‘This is not fun and games. This is big business and, you know, a big deal.’ ”

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Nearly four decades later, however, Thompson says she remains friendly with Fox, seeing him a few times a year at fan conventions. “So, I see him in the weirdest situation ever, which is, like, in front of 3,000 people,” she said. “And sometimes we go out to dinner, the group of us. That’s really nice to see him.”

She also praised the actor, who was diagnosed with Parkinson’s disease in 1991, for his work raising awareness of the disease and money for research via his Michael J. Fox Foundation.

“That’s really special to me because both of my brothers were diagnosed with Parkinson’s a year ago,” Thompson added.