The 1976 film Taxi Driver was directed by Martin Scorsese and written by Paul Schrader. It stars Robert De Niro as Travis Bickle, a veteran working as a taxi driver in New York City who becomes increasingly unstable and frustrated with the crime in the city. Throughout the film, Travis's mental state deteriorates and he decides to take violent action against what he sees as problems. The film explores themes of violence, crime, and Travis's unstable psychological state through its use of color, music, and voiceovers of Travis's diary entries.