 Universal Studios devised a gimmick where moviegoers were not allowed to enter the theater at the moment the football game's two-minute warning began in the film.Due to the film's explicit violence and uncomfortable detail of a homicidal sniper acting alone and without apparent motivation, NBC negotiated with Universal Studios to film additional scenes for its television premiere in 1978.The new scenes would detail an art theft, with the sniper serving as a decoy so robbers could escape without detection.