“To me, Givenchy is a world where women and men alike are strong, stoic and mysterious,” she said in an official statement about the campaign. “They own their power, and share it equally.”

Which means what, in terms of clothes, exactly?

It’s hard to tell from the campaign images, as there are only two garments involved, but at the French Vogue benefit for the Musée Galliera in Paris during the couture shows last week, Ms. Waight Keller seemed to model her own words, appearing in a black tuxedo with an AC/DC T-shirt underneath. With her was the Givenchy communications director Youssef Marquis, in almost the same suit with a black T-shirt.

Besides, mystery is the idea.

The teaser look — previously employed by Anthony Vaccarello when he took the reins from Hedi Slimane at Saint Laurent and by Raf Simons before his first Calvin Klein show — is a way of creating a slow build and buzz around what it is come, as well as serving notice to consumers that there’s a new sheriff in town with new ideas about how to dress. But the dual images also underline the fact that Givenchy is one of the few brands, if not the only one, with sales split 50-50 between men’s and women’s wear.

Beyond the man/woman thing, however, what is significant about the Givenchy images is that there’s nothing particularly perky or daytime-y about them — despite predictions when Ms. Waight Keller’s appointment was announced that her arrival would mean a sunnier, lighter Givenchy than that created by Mr. Tisci over the previous 12 years. Mr. Tisci tended to the goth, and mixed everything from Chola culture to graphic sweatshirts with his chic (making him such a favorite of said Kardashians; he made Kim’s gown for her wedding to Kanye).

Indeed, the looks are steamier and more louche than Ms. Waight Keller’s work over the past six years as creative director of Chloé, where the quintessential image was of a boho-deluxe blonde backlit by the sun. You have to go all the way back to her work as a senior designer at Gucci under Tom Ford, from 2000 to 2005, to remember that she has roots in a sultrier style.