Watching the third film by Vietnamese writer-director Tran Anh Hung is like gazing for a couple of hours at a placid lake on a nearly windless day–the water glistens as if struck by the morning sun, and though there may be swirls and eddies beneath the surface, they make only the slightest ripples. Tran paints a similarly luminous, calm picture of life in Hanoi, hoping that viewers will feel the subtle disturbances occurring among characters who outwardly enjoy lives of almost supernatural serenity and decorum. Most, however, will instead be lulled into near-somnolence by the lapidary, still images floating before them, and some will probably doze off. Though one has to admire to degree of directorial control on display in “The Vertical Ray of the Sun” and the fastidious tastefulness of the execution, the picture is ultimately a remote, emotionally parched piece whose refinement seems curiously at odds with its narrative. Like Tran’s earlier pictures, the film is an extraordinarily elegant work, boasting individual shots so artfully composed that they almost seem ripe for hanging on a museum wall, as well as vibrantly brilliant colors that at times have an almost blinding intensity. While it unquestionably provides a feast for the eye, however, it’s far less successful in dramatic terms. Like Wong Kar-wai’s recent “In the Mood for Love,” the picture is basically a decorous, discreet soap opera, and that’s a contradiction in terms. Like the typical soap, it’s extremely deliberate in its pacing. But conventional soaps are also, by definition, obvious and overwrought. Tran’s film, on the other hand, while measured in the extreme, is cool, detached and almost dispassionate–as well as oblique, elliptical and deliberately mysterious. It’s a picture whose content seems at war with its form, and the result is a frustrating cinematic experience despite the striking care and craftsmanship with which it’s been fashioned.

Set among the intellectual elite in contemporary Vietnam (where it was also shot), the film focuses on four siblings–three sisters and their baby brother–along with their mates, lovers and other acquaintances. The oldest is Suong, who’s married to a photographer named Quoc. They have a young son, but also individual secrets: hers is an apparently long-time lover, and his a second wife, with whom he also has a son. The middle sister, Khan, is also married, but childless; her husband Kien is a writer trying to discover the identity of a man named Toan her deceased mother was once involved with, though no one is quite certain how. The youngest sister, Lien, lives with her brother Hai. Both are romantically involved with others, though not always happily so; moreover, their closeness–they sometimes even share a bed–seems to hint at something that might merely be childish naivete but could be something less innocent. Over the course of two hours these characters (and others) interact, and all of their intersecting problems point back to the marriage of their dead parents, which is remembered as idyllic and perfect but, as Kien’s investigations suggest, might actually have been as flawed as the various couplings in the present.

The overarching theme of “The Vertical Ray of the Sun” is thus the inherently tenuous nature of human relationships, especially those of the romantic variety: though on the surface they might seem harmonious, they’re always rife with hypocrisy, hidden urges and deceptions, and can be ruptured suddenly and without warning. Tran presents that unhappy fact as a reality which inevitably passes from generation to generation. But he chooses to depict it in a fashion that’s dramatically subdued–no one could accuse him of melodramatic excess. Still, the actual narrative isn’t far removed from the stories in afternoon TV serials; it’s just presented in such a dignified, cultivated way that it appears to be more profound than it actually is. If you forget the languid, lovingly rendered, and ostentatiously enigmatic exterior and look into the center of “The Vertical Ray of the Sun,” there’s actually a pretty pulpish heart throbbing there.

Still, the picture is lovely to look at: it turns the environs of Hanoi into picture-postcard perfect locales. One sequence, shot in an area called Halong Bay–it’s where Quoc’s secret wife and son reside–is particularly beautiful, but even such mundane bits as the lengthy, repeated scenes of Lien and Hai going through their morning exercises are designed and shot with an expert eye. The acting is less impressive. The ensemble cast goes through its paces efficiently enough, but generally the performers remain so impassive (deliberately, of course) that the furniture often seems more emotive than they are.

If exquisite craftsmanship is enough to hold your attention, therefore, Tran’s film may capture your fancy. Anyone looking for a deeper, more involving cinematic experience, however, will probably find this “Ray” too slow-moving and emotionally opaque to generate much dramatic heat.