Back to the Future had the potential to look a whole lot different. The beloved 1985 film celebrated its 35th anniversary this year and is coming out with a special Blu-ray set, and ET has this exclusive clip of Ben Stiller auditioning for the role of Marty McFly, which ended up going to Michael J. Fox.
In the clip, Stiller acts out a memorable scene in the film where Marty is on a reluctant date with his mother (Lorraine Baines, played by Lea Thompson).
"Have you ever been, in like, a situation where you know you have to act a certain way but when you get there, you're not sure you can really go through with it?" a nervous Stiller as Marty asks.
Stiller's audition along with those of Jon Cryer, Billy Zane, Peter DeLuise and C. Thomas Howell are included in the Back to the Future: The Ultimate Trilogy set available on 4K Ultra HD for the first time ever on Oct. 20. ET's Nischelle Turner recently spoke with Thompson in connection to the special trilogy set, which is being released just in time to celebrate "Back to the Future Day" on Oct. 21.
"It's crazy!" Thompson marvels at the film turning 35 years old. "It's such a blessing because it was such a great part and I get to really show my acting chops, you know? I feel incredibly blessed to be a part of it."
Thompson also commented on Stiller's audition.
"No wonder he never cast me in anything, he's still mad!" she jokes.
Of course, it's hard to imagine anyone in the role other than Fox. Thompson recalled her favorite on-set memory with him.
"The first day of shooting, I tried to get out of my trailer door and it had been wrapped in crepe paper by about 100 girls who were outside going, 'Ahhh Michael!'" she says with a laugh. "And I was like, 'I get it, I get it.'"
"He's exactly how you think he is," she adds. "He's not fake at all, he's funny, he's disarming, he's humble, he's strong, witty and gracious. He is who you see."
Interestingly enough, Fox also wasn't the first choice to play Marty. Actor Eric Stoltz was originally cast in the part, until director Robert Zemeckis pulled him aside on set and gave him the bad news that things weren't working out.
"It happened so fast," Fox told ET in 2010. "They told me about it, gave me the script, and two days later I was in a parking lot in Pomona with flames between my legs and Chris Lloyd running around like a crazy man."
Back in 1985, Fox revealed the secret to playing Marty during an ET interview.
"What this role called for really was kind of a little peppy, excitable, vulnerable, strange guy who could kind of be cool but goof up," a young Fox said at the time.