Originally entitled "Buenos Aires Affair", Wong Kar Wai's last film before the hand-over of Hong Kong to China comes to the screen in a brilliant burst of magnificent splendour. Like the Chinese title which approximately translates into "Burst of Spring", this film is fresh, vibrant and exciting, harbouring within it a promise of yet more typically "Wong Kar Wai" delights.

Opening with a protracted, raw sex scene between the two male leads, Happy Together tells a (for Wong) fairly linear story of love lost and found. Lai Yiu Fai (the magnetic Tony Leung Chiu Wai) and Ho Wo Ping (a suitably skittish Leslie Cheung) are Hong Kongers on holiday in Argentina, on their way to see the Iguazu Falls. Enroute, they bitch and fight, fall out of love, fall back in love, and finally leave each other high and dry and lost, each struggling to come to terms with their feelings. Forget what you've read about this being Wong's contribution to the current Hong Kong fad: the "gay" movie. This description seriously mars the viewer's perspective. What Wong has done is make a dramatic account of a spectacular love story (arguably his most romantic since the almost overwrought and hyper-romantic "Days of Being Wild"), which just happens to have two male protagonists. Once the initial novelty of the idea wears off, viewers will find themselves caught up in the often messy, sometimes sordid and at other times extraordinarily tender relationship between Lai and Ho.

We first meet the two on a road trip they take to the Falls. Lost and out of cash, Ho walks out on Lai, who finds work as a doorman at a tango bar, trying to save enough money for the trip home to Hong Kong (yes, the irony is clearly intended). By and by, the vain and petulant Ho comes back, first hanging on the arms of the local men whom he prostitutes himself out to, and eventually, back into Lai's reluctantly open arms when he gets beaten up by a john. They set up home for a brief period, rekindling their passion, recapturing their love. In between tango lessons in the bathroom (believe me, it is a lot more erotic on screen than it sounds) and sharing hot meals in the fast cooling weather of Argentina, the jealous and possessive Lai hides Ho's passport, adamant not to let him leave yet again, but Ho refuses to let himself be tied down, and again vanishes into the night. At this point, we are introduced to the third character, a young busboy at the restaurant Lai now works at, Chang (Taiwanese actor Zhang Zhen), who forms a platonic bond with the increasingly frustrated and heartbroken Lai. Eventually, with enough money in hand, Lai leaves Argentina, first stopping at the Iguazu Falls - where his once perfect love would have been complete - to ponder what he's lost, and what he's gained. Chang, meanwhile, heads for the "lighthouse at the end of the world", promising to release all of Lai's sorrow on his behalf once there. On his way back to Hong Kong to face his estranged father, Lai stops at Taiwan and pays a visit to Chang's family, and understands how the younger man's carefree nature stems from his secure familial ties, ties both he and Ho lacked. Meanwhile, stranded back in Argentina, Ho comes undone as visions of the tango he shared with his lover haunt his mind. As the film ends, Lai is on a Taiwanese train, speeding forward as the sounds of "Happy Together" chime on….

Upbeat, positive and life-affirming? Er, not exactly. Although Wong asserts that this is his most hopeful film, one cannot escape the inevitable conclusion that he is a rather depressed man if this is his idea of hope. Yet, almost impossibly, the tone of the film clearly brings forth this assertion. Overcoming the weight of such mechanisms as plot, characterisation and surrounding, Wong's film is indeed a chirpy affair, full of unexpected moments of sheer hilarity (a rarity in all his films) and a decisively upbeat ending full of promise for its main protagonists. In a mood reminiscent of the second part of "ChungKing Express", Wong's story is playful yet serious and sombre at the same time. His script is full of witticisms and makes full effective use of metaphors, as usual. Starkly simple in premise and vision, he imbues the film with a heightened sense of realistic uncertainty by concentrating on the outward manifestations of the men's minds. Lai and Ho are complex and at times, unfathomable, but Wong remains always in control of how the audience sees them. It is a demanding genre, the love story, made more so in this case by having to overcome the public perception of it being a "gay love story" (whatever that means), and Wong's gathered together a bunch of amazing people to fulfil his vision.

Wong is also much aided by William Chang Shu Ping, his long-time editor and aesthetic director. Dressing the actors in costumes suited to their lifestyle orientation (it is such a kick to see the rampantly heterosexual Tony Leung tarted up in skin tight psychedelic print shirts, or the fey, effete Leslie Cheung in an angora sweater), and creating a living space that is reflective of their characters' disintegrating relationship, Chang again affords Wong a stunning visual shorthand, condensing so much information and conveying it within a single frame. His editing here is choppy, abrupt and brilliantly breaks down the seamless, straightforward quality of the story, giving it a rough edge that heightens the emotional pull of every scene. In particular, his effective use of a white-out effect at crucial points of the narrative to reflect how the characters lose sense of their own trains of thought is a stroke of genius which has the added benefit of being visually captivating at the same time.

Like all his other films, Wong's "Happy Together" benefits from a handful of startling performances. New to the Wong "fraternity", Zhang Zhen gives a nicely balanced performance as the potential spoiler of Lai and Ho's love. His role is small, but catalytic, and Zhang knows to give away enough of his character to enable it to propel the story, but still maintain a much needed sense of secrecy so that Chang remains an object of desire to be simultaneously longed for and avoided. Zhang also captures the ambiguous sexuality of Chang wonderfully, so that it is never clear if his friendship with Lai has the potential to become the "something more" that Ho fears it will turn into. A nice deft piece of work.

Less subtle is Leslie Cheung's characterisation of Ho. Trampy, sluttish and pouty, this almost seems like Leslie Cheung, the actor, on screen. Prancing about in garish outfits and obviously revelling in the chance to be showy and coy, Cheung makes Ho a pathetic creature whose sole virtue is his vacillating emotional tie with Lai. Needy at times, hot-headed at others, this is a character that is difficult to pull off simply because it is at once unsympathetic, yet needs empathy with the audience to make them care enough to long for his salvation. It is a denouement Wong denies us, ending his film as he does with Ho trapped in a hellish loneliness of his own doing, but Cheung does occasionally manage to go deeper beyond the surface and surprise the audience with a genuine emotion or two. By and large, he is the weakest link in the cast, caught somewhere between over-acting and not-acting-at-all, and this is his most unsatisfying work with Wong to date. Due to the relative size of his role, his performance does not detract much from the film, but one does wish that he were more effective. Especially when one looks at the extraordinary Tony Leung who makes everyone else in the cast pale in comparison.

As a long time admirer of Leung's work, I do not hesitate to state that this is surely one of his most accomplished efforts to date, even though the actor himself believes he did his best work in the curious final five minute sequence of "Days of Being Wild". Whilst I was watching his performance here, I could not help but think of Leung the boyish actor who made waves more than a decade ago on Hong Kong television as the hot-headed policeman, Kit, in the successful series "Police Cadet", and marvel at how much he has grown as an artist of the craft he practises. The years have consistently added to his maturity and appeal, and in the central role of Lai, he astounds with the depth of characterisation he brings with the sip of a drink, with the simple act of lighting a cigarette. Brutally honest in his portrayal, he allows the audience to feel the full extent of Lai's pain and frustration with the lover he cannot fully possess, and whom he is not entirely sure he would want to fully possess. There is an astonishing scene in the film where Chang hands Lai a tape recorder and asks him to say a few words for him to remember him by; racked with longing for Ho, Lai holds onto the recorder as tears well up in his eyes. It is a remarkably simple scene, made superb by the level of honest emotion that Leung displays - for this all too brief moment alone, "Happy Together" is worth its admission price and more. Thankfully, the film has more of Leung's wonderful performance to anchor it. Wong says that his films are made up of characters, not stories - if so, Leung has created the most memorable male character in Wong's gallery of fascinating portraits of the human psyche, equal in scope and skill to the enigmatic lady (the incomparable) Maggie Cheung played in "Ashes of Time". Faced with such magnetism, it is perhaps inevitable that Leslie Cheung seems less scintillating in his role.

The film brings its characters (and therefore the audience) through the roller coaster ride of emotional highs and lows of the tumultuous affair at the heart of the story. Wong has reached a point in his career where he seems to be able to do no wrong, and this can be a dangerous thing for how can one consistently top one's own achievements? With "Happy Together", he's proven that he has not yet fallen prey to the curse of failing to better himself. We can only hope that this fate does not befall him on his next film, "Summer in Beijing", or indeed, ever.