Travis Bickle is one of the most confused and violent characters ever to grace the screen.  He is an ex-marine who becomes a taxi driver.  He is disgusted by all the filth and scum he sees in New York City, but he drives in the city's worst neighborhoods and picks up the slimiest of characters.  In voice overs, we hear him describe some of the debauchery that goes on in his cab.  He sees a beautiful young woman working in the campaign offices of a Presidential candidate.  He gets up the nerve to ask her out and they go to a luncheonette and have a nice conversation.  Then on another date he takes her to a pornographic movie and she is revolted by this and then spurns him.  One of the heartbreaking scenes in the movie is Travis calling her on a pay phone to apologize.  Martin Scorcese pans away from Travis and shows a long corridor while he is being rejected.  This sends Travis over the edge.  He gets a mohawk and plans an assassination attempt on the candidate which is aborted.  He also meets a 13 year old hooker named Iris.  He can't understand why she subjects herself to this life and why she is with a creepy pimp named Sport.  In the film's bloody climax, Travis kills Sport and ends up in a blood bath while Iris looks on horrified.  Robert De Niro plays Travis as powderkeg waiting to burst.  He lets Travis slowly slide into his own personal hell before finally exploding.  Cybil Shepard is charmingly beautiful as the campaign worker and Albert Brooks provides some levity as her co-worker.  Jodie Foster served noticed as Iris.  She plays the character with seeming self-assurance, but with an underlying fragility an amazing achievement for the then 13 year old.  Peter Boyle plays Wizard, who doles out philosophies on life to Travis, with an all-knowing nature.  Harvey Keitel plays Sport with the right amount heavy handiness and smarm.  The film established Martin Scorcese as a top-flight director.