The original director was Gary Nelson—who had directed the Disney films "Freaky Friday" (1976) and "The Black Hole" (1979)—but he was dismissed from the project after a week of production and was not credited. His replacement, Bruce Malmuth, had only one previous film to his credit: a segment of the 1975 portmanteau comedy, "Fore Play". Malmuth, en route from Los Angeles to New York City, was unable to make the first day of shooting after Nelson's removal and Stallone shot a scene for one day (the chase in the subway). According to the Directors Guild of America, "Anyone signed to work on a movie before the director was engaged cannot replace a fired director, except in an emergency"; arbitration resulted in a fine. In preparation for their roles as New York City police officers, Billy Dee Williams and Sylvester Stallone spent several weeks working at night with the New York Street Crimes Unit.