Great character development film

Rating: 10/10 (26 June 2012)

Starring Robert DeNiro, Jodie Foster, Cybill Shepherd, Harvey Keitel. We gradually realize a Vietnam war veteran (Travis/DeNiro) is becoming increasingly mentally unstable (& with what now might be called PTSD?).
Travis is a night-time taxi driver in New York City. The flagrant prostitution and other decadence he sees around him feeds his urge to violently lash out & he attempts to rescue a young teenage prostitute (Iris/Foster) in his reactive process.
In addition to being in IMDb's top 250, it's also a Roger Ebert "Great Movie." He said, "(it's)....one of the best and most powerful of all films....(and it) does not grow dated or over-familiar"
IMO, all its psychological dynamics are absolutely true to life. The ending has two possible interpretations--one literal, the other's just the last fancy of the injured or dying central character. Scorsese intended the literal view but probably more viewers (as I do) favor the second. Your choice.
There's much of interest we never see--e.g., why Travis developed as he did--but that only increases our fascination. Was he also only a tad mentally unstable as a teenager but his combat experience/PTSD exacerbated this? Or did he seem completely normal and this is the onset of a schizophrenic reaction which typically emerges in this age range? What were his parents and upbringing and teenage socializing like? Etc., etc. The narrative we follow comfortably fits a number of very plausible preceding possibilities.
Most people can read in advance Roger Ebert's reviews of this film and not ruin their enjoyment at all (and may even add to it as it did for me; (of his 3 reviews, I most like the last one he did for his "Great Movies").