PARIS, France — There may well have been a moment of concern when Hedi Slimane left Saint Laurent, but who can even remember it now that it's a billion-dollar-plus business (and growing). Anthony Vaccarello's hard, sexual glamour has clearly connected.

All the evidence you needed was thronging the Trocadero for the Saint Laurent show on Tuesday night, the men in second-skin pants, the women in microskirts, both in glittery little jackets. More or less a mirror of what was on the catwalk, in other words.

Speaking of mirrors, the catwalk was a reflecting pool, and what it reflected was a stand of palm trees bleached a ghostly white. Steam rose around them, like the earth was boiling. It was a strikingly unnatural image, so it suited the striking unnaturalness of Vaccarello's clothing: the tininess, the sheerness, the peculiar interaction of white-lace propriety and black-leather libertinism. He claims it is solidly grounded in Yves Saint Laurent's own work. Even those palm trees were a reminder, Vaccarello added, of YSL's roots in North Africa.

There were so many references to the blueprint here, particularly to Yves’ early 1970s period, when he himself was looking back at the 1940s. Hence, the stars, the stock tie blouses, the leopard print, the hats, the chunky platform shoes…

But Yves was a voluptuary in the grand old manner, with a distinctly adult appreciation of sensual self-indulgence, and there are few designers in fashion now who could match that. So what Vaccarello has introduced to the equation is his own hard-edged style. Chilly, not voluptuous. Rigorous, not joyful, just like the pounding monotone of the soundtrack.

He scores – Adut’s green dress with the big bow in back, an appealing hybrid of a baseball and cadet jacket, a leopard print chiffon caftan – but as I watched the young models splashing through what was presumably quite cold water in their stilettos with parts of their anatomies bared to the cool night air (not to mention the penetrating stares of a thousand humans), I couldn’t help but wonder what they were thinking. I feel powerful? I feel sexy? At least I’m working? (Some of them had belts around their foreheads so maybe they were thinking, "OW.")

Vaccarello is an evolutionary, rather than revolutionary, designer. Season on season, he has adjusted and honed his offering at Saint Laurent. Artful merchandising and marketing does the rest, because that’s how you get to a billion bucks.

But that doesn’t change the fact that the elephant in the room on Tuesday was still Slimane, whose debut at Celine on Friday has been the most talked-about event of the season. Inevitably under Vaccarello’s stewardship, there have been echoes of his predecessor’s reconceptualisation of Saint Laurent, the shorts, the shoes and the stars in Tuesday’s collection being just three examples. No coincidence: both designers drew, after all, from the same archives.

So maybe it was mere fancy that those huge bleached palms, reflected in the mirror pool, looked like some kind of riposte to the Gothic vision of LA that Slimane has explored so strikingly in his photographic work. Hedi’s coming home and Tony’s reminding him who’s The Man now. But hey, ignore that. It’s just me, sittin’ here thinkin’ ‘bout turf wars.