idea ·Taxi Driver (1976)

De Niro wrote in the margins

De Niro's annotated shooting script rewrote Travis's dialogue, and the changes reached Schrader's final draft. The film's most quoted line has no screenwriter.

acting
spoken-language
atomic
authorship

De Niro's shooting script reveals his extensive contributions to the screenplay and various scenes, especially regarding Travis Bickle's dialogue and his interactions with particular actors. These revisions made their way into Schrader's final script version. In fact, De Niro's improvisation resulted in one of the most famous lines in any film where Travis stands in front of the mirror and asks, "Are you talking to me?" This scene is one about which the audience, critics, and Scorsese himself in interviews all agree about De Niro's authorship.

— Aaron Baker — A Companion to Martin Scorsese, smc 316

The Companion treats De Niro's process as a form of authorship in its own right — the performer as soloist interpreting a score, with the notes from Mean Streets and Taxi Driver as documentary evidence of the arrangement being changed (smc 307).

Related, and in the same register: the coffee-shop scene between De Niro and Cybill Shepherd was improvised for about twelve minutes, transcribed, then shot; it runs about three minutes in the finished film (Scorsese on Scorsese (1989), sos 60).

Filed under Acting. See Taxi Driver — the mirror for the scene itself, and Bresson's hands, Travis's guns for the influence that arrived through the writer instead. The useful generalisation: on this film, ask which author before attributing anything.

Go on, then

idea Bresson's hands, Travis's guns The gun-handling sequences copy the pickpocketing in Bresson's Pickpocket. The debt is Schrader's; Scorsese admits he finds Bresson hard to watch.
scene Taxi Driver — the mirror "You talkin' to me?" — the most quoted line in the film is not in the film's script. De Niro wrote it standing up, in a derelict building, over traffic noise.
idea Overhead shots are the priest's-eye view Scorsese's flat overhead inserts come from watching a priest lay out the implements of the Mass on an altar — not from any film.
idea Schrader and Scorsese disagree about the ending Ritual suicide or tabloid item? The writer and the director give incompatible accounts of the same scene, and the film supports both.
idea Bickle sees through glass The windscreen and the rear-view mirror are the film's two apertures. Travis is a viewer before he is an actor, and the film is careful about which passengers he is allowed to see.
idea Chapman pushed the night stock Taxi Driver's wet neon look came from over-developing night-rated Technicolor stock — a 1970s laboratory habit, not a lighting package.