MOVIES : The Meanest Street : Twenty years ago, Martin Scorsese’s ‘Taxi Driver’ knocked us out with its shocking script, gutsy De Niro performance and masterful score. Guess what? It still does.

Even now, two decades after it first appeared, the image remains one of the most arresting openings in modern American film: A yellow Checker cab, massive, unyielding, sinister, pushes its way through a cloud of subterranean New York City steam. From frame one all the way to the end, “Taxi Driver� was a film that never doubted it was going to make an impression.

Written by Paul Schrader, directed by Martin Scorsese and starring Robert De Niro as “God’s lonely man� Travis Bickle, “Taxi Driver� is one of those rare films whose essence has been woven into the fabric of American life, whose protagonist has made his way into national mythology as much as Sam Spade or Walter Mitty.

Never lacking in appreciation (it was nominated for four Oscars, including best picture, and won the Palme d’Or at Cannes), the passage of time has made “Taxi Driver� seem increasingly significant, especially after John Hinckley Jr. shot President Ronald Reagan in a 1981 assassination attempt inspired by the film and apparently intended to impress co-star Jodie Foster.

To mark its 20th anniversary, “Taxi Driver� will be playing at the Nuart in West Los Angeles for two weeks starting Friday. The run is a convenient chance to reexamine one of the best-remembered films of the 1970s, to decide what remains impressive and what does not, and to examine the picture’s much-commented-on violence in light of what has happened on screen from then to now.

Aside from usual tidying up of the negative (the combined work of Sony Pictures Entertainment and New York’s Museum of Modern Art), the biggest news about this “Taxi Driver� is that its score has been remixed and will be heard in stereo for the first time.

That is especially heartening because “Taxi’s� masterful music, both jazzy and insinuating, is the last work completed by one of the irreplaceable giants of movie music, Bernard Herrmann. Best known for his work with Orson Welles and Alfred Hitchcock (“Citizen Kane,� “The Magnificent Ambersons,� “North by Northwest,� “Psycho�), Herrmann in fact died the night after he finished conducting the “Taxi� score, and the film is dedicated to him.

One of the interesting things about “Taxi Driver� seen at this distance is how much a meeting of old and new Hollywood it is, with people like Herrmann and the venerable master of makeup Dick Smith sharing space with Albert Brooks in his film debut and close-to-newcomers like Harvey Keitel as the kinetic pimp Sport and Jodie Foster, not yet 13 when she played the Oscar-nominated role of Iris, the world-weary child prostitute.

In fact, as recounted in Mason Wiley and Damien Bona’s “Inside Oscar,� Foster nearly didn’t get to do the part at all, as the California State Welfare Department objected to someone so young taking on such a seamy assignment. After four hours of psychological tests, Foster--who calmly informed reporters, “Children today know about sex by the time they are 10�--came away with official approval.

Only a few years past his breakthrough picture, 1973’s “Mean Streets,� Scorsese was just beyond newcomer status, still young enough to give himself a Hitchcockian man on the street cameo as well as loose enough to take on the speaking role of a cuckolded passenger when his intended actor didn’t show up.

Collaborating with cameraman Michael Chapman (who went on to do “Raging Bull�), Scorsese gave “Taxi Driver� an intimate, off-the-cuff feeling that would likely mark it as an American independent if it were made today. This was Scorsese before his style got highly polished and overtly self-conscious, when he allowed the excitement he felt about the project to simply appear on screen.

“Taxi Driver� immerses us immediately in Travis Bickle’s troubled world. A Marine veteran who works long hours as a Manhattan cabby just to make the days pass faster and haunts porno theaters on his time off, Bickle confides his thoughts only to his diary, and, via voice-over, to us.

The New York he sees disgusts him; it’s an open sewer filled with the dregs of society. “Some day,� he says ominously, “a real rain will come and wash all this scum off the streets.� Awkward, eager for some sense of purpose, desperate to connect with human society but clueless about how to do it, Bickle is prone to manic fixations, especially where women are concerned.

He first focuses on Betsy (Cybill Shepherd), a coolly beautiful campaign coordinator for a presidential candidate, but Bickle is so at a loss about human behavior he takes her to a porno double-bill on their first date. Then his attention shifts to baby streetwalker Iris (Foster), whom he tries to talk off the streets and back home before resorting to more violent measures.

Naturally, some of “Taxi Driver� has dated, but not as much as might be feared and mostly on the periphery. The presidential campaign subplot comes off as unrealistic, and for a film that felt so completely contemporary when it came out, it’s surprising to see how stuck in the past its costumes look today.

Interestingly enough, the fact that Travis Bickle’s clothing hasn’t dated at all is one of the first things you notice about him. Unlike Albert Brooks’ policy wonk Tom, a prisoner of wide lapels and wider ties, Bickle’s jeans, boots, plaid shirt and army jacket look as unnervingly contemporary now as they did 20 years ago.

And what is joltingly apparent about Travis Bickle two decades after the fact is how timeless a character he is--how, like some kind of shape-shifting demon, he seems as much a part of today’s world as his own, an American archetype with connections to everyone from Kennedy assassin Lee Harvey Oswald to accused Oklahoma City bomber Timothy McVeigh.

Though it’s sometimes neglected when the film is discussed, “Taxi Driver’s� great success wouldn’t have been possible without Paul Schrader’s script, arguably the best he ever wrote.

Numerous sources have been cited by journalists as possible inspirations for the Travis Bickle character, including the films of Robert Bresson, Jean Paul Sartre’s “Nausea,� Ethan Edwards in John Ford’s “The Searchers,� the diaries of Arthur Bremer (the man who shot George Wallace) and even the Harry Chapin song “Taxi.�

But there can be no doubt that it was what Schrader pulled out of himself that made “Taxi Driver� special. Bickle’s mania was not an abstraction to Schrader, it was something he knew from deep inside, understanding the exact dimensions of this demented character in a way that still manages to freeze the blood.

The second part of “Taxi Driver’s� one-two punch is, of course, De Niro’s performance. After the usual initial shock at seeing how young he looks, De Niro’s work retains so much strength and integrity you soon forget who the man is and who he became.

This is classic, burn-a-hole-in-the-screen acting, defining the dislocated homicidal loner for all time just as surely as James Dean and Marlon Brando nailed the different stages of masculine rebellion. From his deceptively easy grin to his involuntary twitches to the inevitable “You looking at me?� monologue, De Niro gives one of the few performances that was as influential as it was impossible to duplicate.

“Taxi Driver’s� ending remains extremely violent, and it is interesting to note that the final blood bath retains its power to shock and provoke even though many films, even several of Scorsese’s own, have exceeded it in graphic explicitness.

Perhaps that’s because “Taxi Driver� uses violence in brief but intense bursts to make thematic points rather than exploiting it to titillate and/or sicken an audience. When Travis Bickle puts his bloody finger to his head and mimics pulling a trigger, that simple gesture has a cumulative power to disturb and unnerve none of this film’s eager successors has been able to match.