The Woman Behind Caitlyn Jenner's Vanity Fair Cover

As dramatic entrances go, it didn't lag far behind that of  Venus emerging from the foam.

On Monday, Vanity Fair magazine, revealing at last a tightly guarded exclusive, introduced the world to Caitlyn Jenner, the transgender Olympian formerly known as Bruce, and gave her the kind of old-style Hollywood glamour treatment that ingenues pine for: a high fashion (if soft focus) Annie Leibovitz cover shoot with the star spilling out of a form-fitting satin corset.

And tasked with outfitting a newly minted glamour girl for the big moment was the magazine's fashion and style director, Jessica Diehl, an industry veteran who styles most of the magazine's cover stars but nevertheless found the prospect "completely petrifying," she said.

Part of the challenge was to present Jenner as the woman she has long wanted to be. "It was really about finding out from Caitlyn what this all means to her," Diehl said by phone on Tuesday. "We talked a lot about what could work in real life, how she sees herself."

They talked icons and inspirations: all-American chic, classic rather than flashy. Diehl brought photos of Lauren Bacall and Jackie Kennedy to a preshoot discussion with Jenner. Diehl wanted to present a range of options and price points. Jenner may yet have the opportunity to be swathed in couture for a glossy's pages, but Diehl made sure she had some cost-effective Diane von Furstenberg looks on hand, too.

The bigger parts of the challenge were the logistics of working largely around the usual protocols. At the magazine, only a "skeleton group" knew of the shoot. (That skeleton crew numbered around 10, Diehl said; she told the rest of her team they were shooting Barbra Streisand.)

Typically, fashion editors will borrow clothing directly from brands; in this case, because of the need for secrecy, Diehl largely resorted to shopping. She scoured Bergdorf's and Barneys, Max Mara and Tom Ford, Michael Kors and DVF, working with Jenner's measurements in mind. What couldn't be sourced in store was sought online. "Online was actually a great boon for us in terms of finding sizing," Diehl said.

Ah, yes: the particular difficulty of getting bustiers and ball gowns for a woman who stands 6-foot-2.

"We all know that a tall woman at 6-2 is not sample size," Diehl said. ("I feel ladies don't ever like to talk about their size, so I would have to defer on that," she said when asked what size Jenner is.)

Most of the women Diehl is called on to dress - say, Jennifer Lawrence, whom Diehl once accessorized with only fine jewelry and a live Colombian red-tailed boa constrictor - are smaller. But, Diehl said, "the one thing that makes it easier to dress someone is proportion. Caitlyn's proportions are fashion proportions, really. She's tall, slim, narrow hipped: kind of ideal to dress."

Diehl had not tried the options on so much as a stand-in before a fitting with Jenner the day before the shoot, but found that everything she brought fit. "That actually never happens to me," she said. "The physique is really extraordinary. We should all be decathletes."

The shoot itself, which took place over several days at Jenner's home in Malibu, California, was a feat of seamless leak-proofing. "There were no cellphones," Diehl said. "They were all in a box. There was nothing."

Vanity Fair also had to forgo its usual outdoor locations, set pieces and props. "Luckily, she has some pretty fierce cars, just in the driveway," Diehl said. "We didn't have to go anywhere." Jenner wore a cherry-red jersey-and-mesh Donna Karan dress in a color-coordinating 2011 Porsche 911 GT3 RS.

That dress, like a few other pieces in the shoot, were sourced with the help of the brands, though never with any indication of the celebrity being dressed. Vanity Fair's usual procedure, several fashion executives said, is cloak-and-dagger, and the prospect of appearing in the issue justifies any perceived risk.

Victor De Vita, the senior manager for global communications and marketing at Zac Posen, sent an off-the-shoulder gown without asking who might wear it, and didn't know it had been used until he saw the photos, with the rest of the world, on Monday morning. Posen said in a statement that he was "very proud to be included in the roster of chosen designers for such a historic moment captured by the iconic Annie Leibovitz."

Likewise, Aliza Licht, the senior vice president for global communications at Donna Karan, helped Diehl track down the Donna Karan dress from the company's South Coast Plaza store in Costa Mesa, California, without any idea whom it was for. Jenner ended up loving it, and got to keep it, a gift from the magazine.

That's a testament to Jenner's happiness with her new look. "That was probably, to me, the most important thing, that Caitlyn feels good about everything," said Diehl, who described Jenner as a partner and collaborator.

"There would have been no way that I would've persuaded Caitlyn in a moment like this - which I can sometimes do, persuade an actress to wear something that I really want her to wear," Diehl said. "This was not the moment for that."