The world of haute couture has been getting a lot of attention on the screen lately, mostly in documentaries, but occasionally in non-fiction form. Yves Saint Laurent, the French designer whose name remains a celebrated brand, has actually gotten the biographical treatment twice recently, first in Jalil Lespert’s “Yves Saint Laurent” with Pierre Niney, which quickly came and went last year, and now in Bertrand Bonello’s “Saint Laurent.” Since excess seems at the heart of the business in which he operated (as well as the way he chose to live his life), the cinematic doubling may be appropriate—and so might the epic running-time of Bonello’s film, which goes on for two-and-a-half hours. But it certainly hasn’t resulted in anything terribly revelatory. Of course, given the fact that couture has everything to do with surface rather than substance, the emptiness of “Saint Laurent” might be an apt commentary on the man. But unless you’re willing to be satisfied with a handsome exterior, you won’t find Bonello’s film very involving, except as a purely visual exercise.

The picture doesn’t provide a full biography—it concentrates on a sliver of Saint Laurent’s life, the years between 1967 and 1976, though it does offer a few allusions to his earlier experiences and adds a substantial segment portraying the days immediately preceding his death in 2008. It opens with a dissipated Saint Laurent (Gabriel Ulliel) checking into a Paris hotel under an assumed name in 1974 and phoning a reporter for a warts-and-all interview (which his partner, the manager of their firm, will seek to squash). Presumably what follows is the substance of what he told the journalist. The film flashes back to 1967, showing Saint Laurent and his staff preparing the collection for the fashion house he’d founded with Pierre Berge (Jeremie Renier) some years earlier. (There’s no mention of his childhood in Algeria or his stint at the house of Dior, though in the introductory interview he does mention his brief period of military service and the psychological turmoil it caused.)

In fashion terms the film then proceeds chronologically through Saint Laurent’s groundbreaking 1976 collection, with its Moroccan overtones, accompanied by occasional visual references to contemporary historical events, like the 1968 Paris riots, to provide context. Throughout there are cuts to Berge’s management of the company, many involving negotiations with the firm’s American partner (Brady Corbet), who at one point objects to a perfume bearing the name of a drug (by this time the suggested intimacy between Saint Laurent and Berge has apparently morphed into something more businesslike), while Yves indulges his creative side and what might be termed his more personal interests.

Within this context Bonello and co-writer Thomas Bidegain insert lots of material portraying Saint Laurent’s flamboyantly hedonistic lifestyle, starting with his interest—primarily artistic, it would seem, with some female models but then delving in earnest into his relationship with nobleman Jacques de Bauscher (Louis Garrel), whose debauchery, at least as presented here, knew no bounds. There are innumerable scenes of them in riotously colorful clubs (in fact they meet in one, in a sequence that has them swooning over one another through the gyrating limbs of dancers), episodes that show them cruising through alleyways and parks, and more intimate moments, filled with sexual activity and drug use. (One result of the latter is the death of Saint Laurent’s beloved dog Moujik, which he will thereafter replace at regular intervals with a succession of canines that are identical copies.)

Interspersed with all this are scenes of the elderly Saint Laurent (Helmut Berger) puttering about his opulent apartment as a valet caters to his every whim and a celebratory exhibition is prepared in his honor. These are juxtaposed, sometimes in split-screen style, with a recreation of the presentation of the groundbreaking 1976 collection. The film ends with newspapermen bickering over the best headline to announce his death in 2008.

Bonello covers all this is glossy style, with Ulliel slinking through the proceedings with an air of surrealistic detachment even when hallucinating under the influence of drugs. Saint Laurent is constantly at the center of things, even when he’s offstage as Berge, played with businesslike straightforwardness by Renier, handles the nuts and bolts of the operation. Garrel, on the other hand, becomes a preening model of decadence as the theatrically over-the-top Bauscher. The rest of the cast is perfectly adequate, though most are used more for looks than dramatic effect. Berger, meanwhile, captures the essence of a man wasted by excess, though the physical resemblance to Ulliel is nil.

What “Saint Laurent” possesses in spades is style, with Katia Wyszkopf’s production design combining with Josee Deshaies’ lustrous cinematography to remarkable effect. Mention must also be made of Anais Romand’s costume design, which mimics Saint Laurent’s creations since permission wasn’t granted to use the originals. An eclectic music score, ranging from classical tidbits to pop tunes, gives the visuals even more oomph, as if any were needed.

As a sumptuous surface treatment of the man who for a time seemed to embody high fashion in all its glitzy excess, “Saint Laurent” does the job. But anyone looking for a Rosebud to explain his combination of creativity and self-destructiveness won’t find it here.