8 Little-Known Back to the Future Facts That Are Cooler Than a Time Machine

It's no secret that actor Eric Stoltz filmed the role of Marty McFly for about nine weeks before being fired. They replaced him with the star they wanted all along — Michael J. Fox — but before everything worked out, Eric caused a bit of tension on set. During the scene where Marty pushes Biff in the cafeteria, Eric did it with such force that Thomas had to tell him that he would react just as realistically if he backed off. Eric continued to push Thomas hard, and despite him warning him more than once, Thomas ended up with bruises on his chest.