Full Metal Jacket
R. Lee Ermey plays an unforgettable drill sergeant in Stanley Kubrick’s classic film Full Metal Jacket. What’s surprising is that he wasn’t supposed to be in the movie at all, and he sent Kubrick a video he filmed at home of him shouting at and insulting Marines. He later admitted that nearly half of his lines were improvised.
Sometimes mistakes become a vital part of a film. These mistakes can include natural reactions as well. For example, Dustin Hoffman’s real reaction while crossing a street during the filming of Midnight Cowboy has become one of the most recognizable lines in film history: “I’m walkin’ here!” He shouted this out when a taxi driver nearly ran him and Jon Voight over!