Fans of Michael J. Fox as Marty McFly will want to watch the clip below from the bonus features of the Back to the Future 25th Anniversary Trilogy collection out Oct. 26. We get a peek at what the movie would have looked like if director Robert Zemeckis didn’t realize after five weeks of filming that Eric Stoltz, who was originally cast as the teen time traveler, had different “comedy sensibilities” than himself and his co-writer Bob Gale. As executive producer Steven Spielberg recalls in the clip, Zemeckis showed him some footage and said he didn’t think they were getting the kind of laughs they wanted. Zemeckis had to make what he refers to as the “horrific decision” to recast the role after the studio agreed to let him reshoot those five weeks worth of film. Stoltz, of course, went on to get his big break in 1985’s Mask — and both he and Fox earned Golden Globe nominations that year.

While you ponder a Back to the Future with Eric Stoltz, think back to all the trivia you’ve collected on beloved ’80s films over the years and share your favorite “could’ve been” stories. I’ll start: We’re still waiting for 1989’s Weekend at Bernie’s to get a tricked-out DVD release, so when the movie hit shelves in 2005 with the trailer as the only bonus feature, we phoned Jonathan Silverman to create our own extras. He told us it was supposed to costar Jon Cryer, not Andrew McCarthy: “They had us screen-test for both roles, so all we knew was that one of us would be playing [Richard] and the other would be playing [Larry], and we’d start shooting in a few weeks,” Silverman said. “I’m not sure what happened. Then it became me and Andrew.” Another ’80s classic that could’ve been different? 1986’s Pretty in Pink. According to the 20th Anniversary DVD, the role of Blane was originally scripted as a square-jawed jock for which Charlie Sheen was considered — not McCarthy. And as for Duckie, Robert Downey Jr. was up for the part, which Cryer has admitted he didn’t know at the time. “I knew Fisher Stevens was up for it,” he told EW in 2006, “because he and I were hopping from show to show: He was doing Torch Song and I was doing Brighton Beach, and then I was doing Torch Song and he was doing Brighton Beach. There was this whole cottage industry of young male actors who were, basically, either understudying for or taking roles from Matthew Broderick at the time. And knowing that Fisher was a really tremendously gifted guy, I thought, Oh, I’m in trouble.” Your turn!