Lea Thompson has shared that her initial interactions with Michael J. Fox on the set of 'Back to the Future' were marked by tension due to her friendship with Eric Stoltz, who was originally cast as Marty McFly. Thompson admitted to being 'snooty' towards Fox, perceiving a divide between movie and TV actors at the time, as she had previously worked with Stoltz. Despite her initial reservations, she acknowledged that it took time for her to warm up to Fox, who ultimately brought a unique comedic energy to the film. Director Robert Zemeckis had initially cast Stoltz but quickly realized the actor was not fitting for the role, leading to Fox's eventual hiring. Thompson's experiences highlight the evolving dynamics on set, which transformed into a strong working relationship as filming progressed. Reflecting on the impact of the film, Thompson emphasized its enduring popularity and significance in family storytelling.