The 1976 thriller film directed by Martin Scorsese, "Taxi Driver," features Robert De Niro in a memorable role where he delivers the iconic line, "You talkin' to me?" The film revolves around Travis Bickle, a mentally unstable Vietnam War veteran turned taxi driver in New York City. As Travis spirals into a violent and obsessive state, he practices confronting imaginary adversaries in front of the mirror, leading to the now legendary line. De Niro's intense delivery and the line's subsequent cultural impact have cemented it as one of the most recognizable quotes in cinema history.