The line “You talkin’ to me?” appears nowhere in Paul Schrader’s original screenplay for Martin Scorsese’s 1976 drama; neither does the scene that follows, as Robert De Niro’s Travis Bickle glares into his mirror, imagines himself taking on a random attacker, and practices responding with words and force. The scene was the result of a lengthy on-set improvisation by De Niro, with encouragement from Scorsese, who was inspired by a scene of Marlon Brando talking to himself in front of a mirror in the 1967 film Reflections in a Golden Eye. This would become Taxi Driver’s most famous scene, making “You talkin’ to me?” the go-to line for De Niro impersonators to this day.