ate one night in March of last year, in a crumbling area on the island of Macao off Hong Kong, a film crew milled around in the street, awaiting the arrival of Wong Kar-wai. In life as in art, Wong tends to make you acutely aware of time. His films are filled with clocks and calendars. He is also notorious for keeping people waiting: waiting for his films to go into production, waiting for the shooting day to begin and waiting for a recognizable story and structure to emerge from his long, uncertain process. This particular night, the crew was setting up to shoot scenes from Wong's eighth film, ''2046,'' an ambitious, star-studded, futuristic drama. (Its title refers to the 49th year after the 1997 British handover of Hong Kong.) There was nothing futuristic about the location: a dilapidated block bathed in a latticework of shadows and artificial golden light, it resembled the 1960's Hong Kong the director conjured for his previous film, the acclaimed ''In the Mood for Love.''

Shortly after midnight, a minivan pulled up, and Wong stepped out, clutching a sheaf of pages on which he had written out in longhand the next scenes to be shot. Copies were quickly distributed by an assistant director. If it appeared that Wong had arrived straight from a session of coffee-shop scribbling with a quick stop at Kinko's, the truth was not far off. Although shooting in Macao had required giving his company a few days' notice, Wong's standard M.O. is to tell actors a starting time and location as close to the last minute as possible. Nor does he tend to give them any dialogue or the specifics of a scene until it's time to shoot; instead, he rolls the camera, thrusting them into situations with which they have only just been presented.

A boarded-up shop off the street served as a dressing room. Wong's production designer and costumer, William Chang Suk-ping, adjusted the hair and clothing of the film's leading man, Tony Leung Chiu-wai, as Leung skimmed the pages. ''I'm the only one that can read Kar-wai's handwriting,'' Leung told me. ''So I always have to explain the dialogue to everyone else.'' His character hadn't been given a name yet, so his lines were simply slugged ''Wai,'' a diminutive of his Chinese name. In ''Mood for Love,'' Leung had played Chow Mo-wan, a lovesick writer. In ''2046'' he was also playing a writer, but this time, Wong had instructed him to behave like a ''Bukowski character,'' a heartless, careless, down-at-the heels gambler and Lothario. He read aloud the description of a scene coming up -- ''Interior, motel, making love'' -- then happily exclaimed, ''So many sex scenes in this movie!'' Chang chuckled.

When the camera and lighting were set, Wong walked Leung through the shot with his costar Zhang Ziyi, the actress best known for her portrayal of an alluringly feisty young swordswoman in ''Crouching Tiger, Hidden Dragon,'' and who portrays a fashionable dance-hall hostess in ''2046.'' Then the camera rolled, Leung and Zhang walked slowly along the deserted sidewalk, talking and laughing. An assistant director translated the dialogue for me: Leung was telling Zhang that he has enjoyed the time he's spent with her, but that it was time for him to go. A heaviness suddenly settled upon Zhang, and when they embraced she broke into sobs.

''Where is he going?'' I asked the assistant director.

''Oh, we don't know,'' she said.

''No one knows where he's going or why?''

She shrugged: ''That's the ambiguity of the script.''

The kind of person who might once have proclaimed ''Jules and Jim'' or ''Wings of Desire'' his or her favorite movie now rates Wong Kar-wai at the top of the list. Flirting with the conventions of genre (melodrama in ''Days of Being Wild''; Chinese swordsman adventures in ''Ashes of Time''; Hong Kong action movies in ''Chungking Express'' and ''Fallen Angels''), his meditative, pop-savvy films home in on emotional tipping points in the lives of young city-dwellers -- the moments that forever mark them and from which they cannot escape. Their witty invention, color-drenched visuals and romantic longing offer the kind of bittersweet satisfaction found in the fiction of Haruki Murakami or the photographs of William Gedney, about whose subjects John Cage once said, ''They seem to be doing happy things sadly, or maybe they're doing sad things happily.''

Among living directors, Martin Scorsese is the filmmaker Wong Kar-wai most admires. And just as the artistic innovations of Scorsese, and before him Godard and Fellini, were systematically plundered by other makers of films, TV commercials and music videos, Wong's signature moves have rapidly been assimilated over the past decade. Even if you have never seen a Wong Kar-wai film, you would recognize his style. For attentive fans, going to the movies has become a game of ''spot the Wong Kar-wai tribute'' (or rip-off), with a diverse list of directors explicitly recreating shots, scenes or musical cues from his work, including Spike Jonze in ''Adaptation,'' Cameron Crowe in ''Vanilla Sky'' and Jean-Pierre Jeunet in ''Amelie.'' Scorsese himself modeled the battle scenes in ''Gangs of New York'' after those in Wong's hallucinatory ''Ashes of Time,'' and even Sam Raimi in ''Spider-Man 2'' sends Tobey Maguire and Kirsten Dunst for a quick stroll through a Chinatown that manages to look more like Wong Kar-wai's Hong Kong than New York.

The melancholy of loss and separation that pervades Wong's work would seem to come naturally. Born in Shanghai in 1958, he emigrated to Hong Kong with his parents at the age of 5, leaving behind an older brother and sister. The circumstances of the Cultural Revolution kept Wong from seeing them again for more than a decade. A lonely child, he didn't speak the local Cantonese dialect until the age of 13. He spent afternoons accompanying his mother to the movies, and he sometimes followed his father, a nightclub manager, on his nocturnal rounds, developing an ongoing fascination for scruffy urban lowlife, jukeboxes and polyglot pop culture.

Wong enrolled in art school but dropped out to join a screenwriters' training program in 1980. Supported in part by his wife, Wong then struggled in the lower echelons of Hong Kong's film industry for nearly a decade before directing his own work. A chain-smoking design junkie and bookworm, Wong cultivates a certain elusiveness in public: the mysterious dreamer, always in sunglasses, given to laconic or cryptic pronouncements. One on one, however, he is personable and direct, with a ready streak of goofball humor and disarming personal charm. That quality is especially important when he needs to persuade people to finance films without scripts, or modest Chinese actresses to overcome their inhibitions before a sex scene.

The international success of ''In the Mood for Love'' has given Wong the chance to put his imprimatur on some high-profile commercial pursuits. He supervised a worldwide advertising campaign for Lacoste and directed a short film for the BMW series ''The Hire.'' But making his own films remains a continuing struggle -- in part because of his quixotic insistence on working the way he does.

riginally, Wong wanted to try to put his stamp on the science-fiction genre, so ''2046'' was conceived as a futuristic thriller. Filming began in 1999 in Bangkok during a break in the lengthy production of ''In the Mood for Love,'' but ''2046'' was then put aside. In the intervening years its imminent completion was announced and postponed so many times that it became a running joke in the Asian press that the film wouldn't be finished until the year of its title. Wong completed the film in time for this year's Cannes Film Festival but then continued to work on it, declining an invitation to show ''2046'' next week at the New York Film Festival, where he has long been a favorite. After presenting the American premiere of each of his films for the past decade, this year's festival will be marked as much by the absence of ''2046'' as it would have been by its presence.

Closer to Wong's home, however, on Sept. 28, just before China's National Day holiday, ''2046'' will finally have its premiere across mainland China and in Hong Kong; Japanese and European releases will follow throughout the fall, and when the companies currently vying for North American rights finish duking it out, audiences in the United States should get to see it sometime next year.

When they do, it will no longer be a futuristic thriller, but something more complicated and personal -- a story set only partly in the future and primarily in 1960's Hong Kong, the milieu of Wong's childhood. The title ''2046'' originated as shorthand for the Chinese government's assurances to the people of Hong Kong that the territory would remain autonomous and unchanged for 50 years. Wong hoped that the film would be a fresh way for him to approach his favorite subjects: the passing of time, the possibility of change and, as he put it, ''broken promises.''

When he returned to the project after completing ''Mood,'' Wong felt the idea of projecting Hong Kong 50 years into the future seemed too literal and one-note. He spent 2000 and 2001 reconceiving the film, signing new cast members and announcing restart dates in locations as disparate as Bangkok, Shanghai and Pusan, South Korea. But each time he had to postpone as financing fell out, actors became unavailable and shooting permits became entangled in red tape. ''I already forget how many versions of the film have existed,'' Wong said recently. ''Each time if we are able to shoot the film, we would 'finish' the film -- but it would be a different film.''

At the same time, ''In the Mood for Love'' proved to be Wong's breakout movie. He had always seen ''Mood'' and ''2046'' as companion pieces, past and future. Now he began to think that ''2046'' might be a continuation of the first film. Rather than playing a futuristic postman as originally planned, Leung would once again play a writer in 60's Hong Kong -- but this time his subject would be science fiction rather than martial arts. The film would therefore intercut scenes from the many affairs of Leung's womanizing character with episodes from his stories (using material from the 1999 shoot and other scenes that would be shot on massive sets built in Shanghai); the same actors would be used to portray characters in both the 60's and 2046. Even then, Wong wasn't sure whether to have Leung reprise the role of Chow Mo-wan. To preserve the possibility, he began shooting the film without having anyone refer to the character by name. This sort of extreme indeterminacy is always in play.

Other directors have employed similar strategies: D.W. Griffith directed the three-hour historical spectacle ''Intolerance'' without a script in evidence; since then, John Cassavetes, Robert Altman and Mike Leigh have used various improvisational methods. Wong Kar-wai, however, approaches filmmaking the way a writer composes a novel, trying out new things on a daily basis, which he feels free to scrap or redo later; he shoots contradictory scenes that require his actors not to hold to any particularly fixed idea of character or plot; he experiments with different visual approaches. In short, he keeps his options open, almost insanely so, in order to discover the movie as it progresses.

When I joined him, nearly a month into the new production last year, the film was taking place in 1967; Tony Leung, who might or might not be Chow Mo-wan, was living in Room 2047 of a dingy hot-sheets motel and serially getting it on with a handful of women passing through Room 2046 next door. Concentrating first on Leung's character's relationship with Zhang Ziyi, Wong wanted to see where it would take him.

Wong and company had taken an abandoned warren of rooms and transformed them into the decrepit Oriental Hotel, its interiors decorated in fading layers of deep green, brown and black, with walls that looked pockmarked and scuffed like a Jackson Pollock painting. One night, I squeezed into Tony Leung's crowded quarters. The camera, mounted on a set of ceiling tracks, pointed down at Leung's cluttered, cigarette-strewn writing desk. The shot would be from overhead, one of Wong's classically atmospheric moments, with Leung, bathed in a small pool of light, scribbling in a late-night frenzy, then pausing, staring at the ceiling and exhaling a cloud of smoke.

Wong sat at the video monitor, his own ashtray overflowing, considering the composition: should the desk be balanced in the frame or off-axis? Should he start close and pull back, or zoom in? It was a single shot that would comprise less than a minute of screen time, but it was precisely what Wong's films are known for, the perfect distillation of an ineffable emotional moment.

Leung came in and the camera rolled: Wong's cinematographer, Christopher Doyle, a wiry 50-year-old with bright blue eyes and a shock of mad-scientist hair, simultaneously zoomed out and moved the camera for a kind of reverse corkscrew effect, from closer in to a stopping-point near the ceiling. Leung exhaled and Wong called ''Cut,'' critiquing the shot in a stream of Mandarin that concluded with a pronouncement in English: ''Not. Creative. Enough.''

''I know. . . . '' Doyle shot back. ''It's my first day on the job.'' Doyle and Wong often trade barbs like a couple. Frequently, after Doyle has set up and lighted something stunning or laid out a complicated but efficient move, Wong's deadpan comment will be, ''Is that the best you can do, Chris?''

The mercurial Doyle, hot to Wong's cool, is one of the world's foremost cameramen, in large part owing to his complicated and fruitful relationship with Wong that dates back to 1989, when they were shooting ''Days of Being Wild.'' Australian by birth, Doyle has lived in China for nearly 25 years, devoting most of his career to photographing Asian films. He is constantly in motion, spouting a running, Heineken-fueled stream-of-consciousness monologue. The visual hallmarks of Wong Kar-wai's films owe much to the extraordinary sensitivity of his eye. An exceptional writer, Doyle has also published books about his collaborations with Wong and others. ''The way the film looks is its reality,'' he writes. '''Based on a true story' is such a lie. 'Based on a true color' or 'based on a strange dream' is what films cry out to be.''

Equally crucial to the development and evolution of Wong's work is Chang, the soft-spoken, 49-year-old production designer and costumer on all of his films. The mesmerizing wallpaper, spectacular dresses and artful ambient erosion are all his doing. Wong Kar-wai will say no more than ''Zhang Ziyi is a dance-hall hostess'' and leave the rest to Chang, whose approach is as intuitive and improvisational as the director's and carries just as much weight. After shooting for several days in one of the Oriental Hotel's hallways, Chang decided it should have a red curtain hanging from the ceiling, effectively forcing everything that had been shot there to be redone. The result of Chang's exactitude, especially for actresses, is the attainment of a near iconic level of numinous beauty.

Chang is also the editor of Wong's films, providing much of the construction and tempo of the final product. On most films, editing begins in earnest once shooting has stopped; with Wong Kar-wai's films, shooting, cutting and writing all continue at once -- sometimes overlapping, other times in stop-start alternation. One afternoon last year, I sat with Chang as he reviewed selected takes from a high-spirited bed scene between Tony Leung and Zhang Ziyi. Chang leaned forward on the sofa, elbows on knees, holding his chin, staring at the screen as an assistant ran the assemblage. He usually begins working with the footage as soon as it's shot, looking for a scene that resonates. After identifying it, he builds out, letting other material follow its lead.

Chang admitted that he had yet to find his way in. ''It's strange because they're so many actors, actresses,'' he said, referring to the various relationships in which Leung's character becomes entangled. ''Usually after two weeks I have a feeling of mastering the story. But right now I don't have that feeling.'' Confident that an answer would eventually emerge, Wong didn't pressure him.

Like Miles Davis, whose best groups gathered distinctive soloists who were also composers in their own right, Wong extends his collaborators a tremendous amount of freedom and then selects what suits him. Spontaneity is prized: Doyle would rather have an unmediated response to the space in which he's filming than know too much about the story; Chang waits until the last possible minute before presenting color schemes or costumes to Wong. The payoff of their interplay is a palpable immediacy -- a sense that you're seeing things onscreen as they unfold.

Wong also knows the value of withholding. He refrains from giving his opinion or approval as a way of getting actors and collaborators to offer more in an attempt to please him. When he finally responds, it has the effect of redoubling their efforts. On set, he often assumes a kind of experimental detachment, looking to try every kind of tonal or technical variation. This can be time-consuming and maddening; it can also be fun. Frequently, he'll give no explicit direction to an actor beyond playing him a piece of music and asking him to enact its mood. Wong simply believes the right thing isn't something that can be imagined beforehand, but only discovered.

Actors, however, can lose confidence in the process. Five years ago, Takuya Kimura , a Japanese superstar musician and actor, was tapped by Wong to play a leading role as a hit man in the original Bangkok production of ''2046.'' He was a fan of Wong's films but had only experienced the regimented Japanese system of film production. Kimura was flummoxed during his weeks on the set. He had expected to act opposite the Chinese pop diva Faye Wong, but Wong instead asked him to improvise scenes with a cow, a pig and an elephant. On his radio show in Japan, Kimura mocked the chaotic production and said he wasn't sure if he was interested in coming back.

Even stalwarts like Maggie Cheung, whose reputation as a serious actress was established in Wong's early films, find their patience tested. After being told on three separate occasions that her part in ''Mood'' had wrapped, she was summoned back from her home in Paris for additional reshoots and vowed never to work with Wong again. She recanted when she saw the film.

''Mood'' also caused a serious rift between Wong and Doyle when the cinematographer's commitment to a Hollywood film forced him to leave after more than a year in production. After devoting months to experimentation before settling on a visual approach, both men were unhappy when Doyle's work had to be completed by Mark Li Ping-bin. Because Wong had taken so long to find what he wanted, the majority of the finished film was shot in a frenzied six-week run-up to its premiere. Although its look owes nearly everything to Doyle, more than half of it was photographed by Li. (The two share credit.) Doyle and Wong barely spoke for a year.

To critics and detractors, Wong is undisciplined, wasteful and disingenuous. Asked about the tension his habitual brinksmanship creates, he answers philosophically: ''I can understand why that happens. But . . . everyone knows: this is how I work.'' It's his version of the old Popeye creed: I yam what I yam. But from an artistic standpoint, the question Wong poses is whether his results can be achieved in any other way. Last year, when Nicole Kidman sought Wong out to discuss working together, he warned her about how much time and uncertainty would be involved, and she came away even more eager to act for him.

In mid-March of last year, the SARS epidemic, which shut down Hong Kong for several months, interrupted ''2046'' yet another time. After some days of additional shooting in early summer, Wong could not begin again until last fall, when the company moved to Shanghai for the scenes set in the future. Returning to Hong Kong at Christmas, they wound up shooting through April of this year.

As a result, ''2046'' was the first film in Cannes history to arrive so late that the schedule of competition films had to be rearranged. The print, fresh from a lab in Paris, was escorted from the Nice airport by police motorcade, arriving less than three hours before its delayed premiere.

The version screened at Cannes was lush and strange, contrasting the scuffed-up, dark colors of the 60's with the baroque, pulsating, green and orange interiors of Tony Leung's imaginary future: Room 2046 of the ramshackle Oriental Hotel functions as the portal to a speeding bullet train called 2046 and a gleaming metropolis of the same name. Not long after shooting the scenes I'd witnessed, Wong decided that Tony Leung's character would be Chow Mo-wan, making his ill-fated affair with Maggie Cheung of ''In the Mood for Love'' part of his transformation into a cad.

Besides Zhang Ziyi, Leung takes up with a string of other women: Faye Wong, who plays both the daughter of the Oriental Hotel's proprietor and a robot in his science-fiction stories; a doomed lounge singer played by Carina Lau; and Gong Li, as a mysterious gambler dressed in black. Unable to form lasting connections in the mid-60's episodes, he writes obsessively; transposing scenes from his unhappy life into his stories, Tony Leung's character tries to inscribe himself into a future where things might be different, making a plaintive declaration: ''I need to change.''

Last fall, Kimura, the Japanese superstar, now four years older, returned to the film. Assuaged by Wong, he now appears as Tony Leung's avatar. At the Cannes premiere, Kimura remained puzzled about how it would all work, but he emerged a typical convert. ''The film is beautiful,'' he marveled. ''There's a beautiful sadness.''

A different kind of sadness comes with the news that once again Wong and Doyle have parted ways. Neither man will discuss the split, but Doyle left the production in January, and the film credits two additional cinematographers: Doyle's former assistant Lai Yiu-fai and Kwan Pun-leung. While it's by no means impossible that the two might reconcile, this may very well mark the end of their partnership.

After Cannes, Wong declined further festival invitations, completing special-effects shots, shooting additional scenes and revising the film's beginning and end. In mid-August, he emerged to announce its final completion. The new version has not been screened yet, but where the Cannes version ended with Leung's character surveying his past and once again declaring, ''I need to change,'' Wong hints that he has since found a way to bring his protagonist's impasse to some resolution.

It may be a lazy deconstructivist's cliche to read every text as an allegory of its own making, but on some level, ''2046'' invites it: one passage from Leung's novel ''2046'' reads: ''2046 is a hard train to get off. How long have I been on this train?'' Wong himself allows that the film, like Fellini's ''8 1/2,'' has turned into a midcareer retrospective. Depicting Leung as a man unable to let go of his past, Wong has filled ''2046'' with deliberate allusions to his previous films. Setting out to make a science-fiction film, looking into the future, Wong discovered that he needed to face backward as well.

Why does Wong Kar-wai keep circling back to Hong Kong in the 1960's, first in ''In the Mood for Love'' (which began filming as a contemporary story), and now in his latest film? If there is a ''Rosebud'' at the heart of his career, it is his second film, ''Days of Being Wild,'' a melodramatic memory play featuring a large ensemble, set in Hong Kong in 1960. Ambitiously conceived in two parts, its high cost and resounding commercial failure kept the second half, which was to take place in 1966, from ever being made. In an ingenious stroke, ''2046'' winds up completing the story begun in ''Days of Being Wild.'' Like the inhabitants of Garcia Marquez's Macondo or Balzac's Paris, Wong's characters turn out to inhabit a dense overlapping universe in a fantastic chain of desire, rejection and loss. ''In the process of making this film,'' Wong e-mailed me not long ago from the editing room, ''I never thought I wouldn't complete it. Sometimes I was tempted to look for an easy way out.'' Now, the burden of the past -- not just Chow Mo-wan's, but Wong Kar-wai's as well -- has been lifted, and Wong himself can perhaps move on.

What form that will take remains uncertain. However, in a bold departure, Wong recently agreed to develop and produce three English-language films for Fox Searchlight. He's not sure that he'll direct any of them, but selecting and working with other screenwriters and directors will be a new experiment. He is not likely to abandon his improvisational method, but he says he would like to find ways to be more productive. Perhaps working from a script, (one of the Searchlight projects) or making a film based on real events (he has been developing a project for Leung about the Hong Kong man who trained Bruce Lee) might provide a stronger tether to keep the director from losing himself amid the infinite possibilities. As ever, Wong Kar-wai is willing to explore his options.