Jason Wu said he was feeling Zen, swiveling in an office chair in his studio near Penn Station.

It was Saturday afternoon, the day before his runway show, and he was surrounded by his design team and stylists, fitting models in outfits from his spring 2021 collection. The clothes were bright and breezy; the waists were elastic, the bras were cashmere, the hats were big, and the sandals were flat.

He thumbed through his phone, looking for a video of one of the models walking down a rural tree-lined road that he’d been sent the day before. He approved the casting via text, and today she was here, he explained with some awe.

The models came and went, floating from their fittings to their Deborah Lippmann manicures in an adjacent room, which Mr. Wu called “the spa.” Jazz played from a speaker somewhere. There was still a lot to do, but nothing felt too intense.

“I think this might be my favorite show ever,” Mr. Wu said.

It may have also been his strangest. This season, Mr. Wu was one of the very few designers staging a traditional runway show during New York Fashion Week. The pandemic has driven most designers online, offering videos and look books (dressed up as “digital activations”) in lieu of shows. But not Mr. Wu, who debuted at NYFW 14 years ago, when he was just 23.

Mr. Wu had also decided to show his contemporary line on the runway for the first time, rather than his more glamorous Jason Wu Collection, with its evening looks and Manolo Blahnik heels. Mr. Wu’s gowns rose to prominence when Michelle Obama wore them to both of her husband’s inaugural balls. He still routinely dresses celebrities for red carpet events — not that there have been many of those this year.

Maybe this was the source of Mr. Wu’s Zen; for once he was showing caftans instead of formal wear. Or maybe it was that, as he put it, “this isn’t my first rodeo.” Either way, his tranquillity on Saturday belied the high stakes of Sunday.

The future of fashion weeks is unclear. Traditional runways shows are petri dishes stuffed with spectators, no one knows how long pandemic restrictions will hinder international travel or dictate the parameters of events, and even though thousands of people depend on the work provided by fashion shows, many designers are sick of doing so many of them.

To host a show now, when practically no one else in New York will, is to declare that the runway still matters — that even in a pandemic, it is worthwhile. And to make that declaration convincing, it’s simply got to be good.

How to Construct a Concrete Jungle

Mr. Wu decided to go forward with a runway show in July. It was partly his hometown pride; he felt that New York Fashion Week, which has slowed down in recent years, still needed to be represented on the international calendar, “through the good times and not so good times.”

“The pandemic is still very much a reality,” he said. “But I think, as companies and creators, we kind of have to just hunker down and make a decision. Like, are we going to keep creating, or not?”

He had also been presented with an interesting sponsorship opportunity. Lowe’s Home Improvement was teaming up with NYFW and would provide the materials for his set.

There was also the fact that a show in a pandemic would surely attract more attention than a show in a normal season, when Mr. Wu had to compete with names like Ralph Lauren, Marc Jacobs, Michael Kors and Oscar de la Renta (all of whom were skipping NYFW this season). In February, Mr. Wu’s show had been scheduled in the middle of the Academy Awards, one of fashion’s most high-profile events.

“I guess the pressure is on,” he said during a phone call in late August, laughing a little but not a lot.

The show would be executed by Focus, the internal production company of IMG, the owner and operator of NYFW: the Shows, which was standing firmly behind doing physical events this season.

“We truly believe in the physical format,” said Leslie Russo, the executive vice president of IMG’s fashion events group. “Whether that physical format evolves remains to be seen. I think people love a runway show. I think people love sitting in the front row.”

The theme of the show would be Tulum, Mexico, one of Mr. Wu’s favorite vacation spots and the location of his 2016 wedding. This was convenient, considering the show would need to take place outdoors. After months of discussions with IMG, Gov. Andrew M. Cuomo allowed New York Fashion Week to go forward with live audiences only if events were outdoors and attendance was capped at 50 people. Indoor events were prohibited from having spectators.

This summer, Dominic Kaffka, the Focus head of production, presented Mr. Wu with a plan to transform the rooftop terrace of Spring Studios in TriBeCa — a common site for indoor shows — into a kind of socially distant jungle beach.

“I think you can definitely interpret it as escapism,” Mr. Kaffka said right after Mr. Wu signed off on the design plan, about three weeks before the show. “You go to the beach, you’re in Tulum, you have a drink, no worries. That’s what I think we’re trying to recreate, for at least one evening.”

Guests at the show would include 30 or so of Mr. Wu’s friends, along with industry figures and a few fashion editors. “It’s going to be very, very exclusive and very private,” Mr. Kaffka promised. But the show would also be streamed online, and the challenge would be giving the masses a feeling of escapism, too.

The more obvious and pressing task, however, was pulling off any kind of event under the strict safety requirements. Everyone working on the show — set builders, interns, models — would not only need to be screened with thermometer guns, but also present negative Covid-19 test results before being allowed in the building.

Still, there was something refreshing about working under such tight rules and strange circumstances, Mr. Kaffka said. Runway shows have a formula: They’re less than 10 minutes long, in front of 300 people, and location is everything

“Every six months, the same group gets on the same planes and watches the same shows,” he said. “It was extremely stimulating this season to be forced to do something else.”

Nine Minutes

Three days before Mr. Wu’s show, it rained all day in New York City. Mr. Kaffka’s team watched closely as Sunday’s forecast showed precipitation, too. Rain itself wasn’t a big deal, he said; guests could be given clear umbrellas, and some humidity would only make the jungle feel more realistic. But if the rain turned into a thunderstorm, they would have to look into a scheduling change. Moving the show inside was not an option.

“We love to create a perfect moment, and it can only be perfect if there’s a certain risk that things can go wrong,” he said. “That’s the beauty of it.”

But the fashion gods smized upon Lower Manhattan. The forecast cleared, and late on Friday night, construction began. The rooftop terrace’s restaurant was stripped away to make room for a few tons of playground sand and hundreds of tropical plants. (The number ranged from 850 to 1,000, depending on who and when you asked.)

Plastic sand bags and brown paper-wrapped palm trees were stuffed into two freight elevators, then lifted to the seventh-floor roof, where several masked construction workers waited to unload them. This alone took about eight hours. Then the work began of arranging the plants and props (like coconuts) into a landscape with some enclaves carved out for hidden camera operators.

Twenty-four hours before showtime, Mr. Wu arrived to check on the progress. As the elevators opened up, a camera crew closed in, following him as he walked down a lush aisle that eventually opened up into a sandy flat. Wooden chairs would be placed here for the audience, framing the curved runway and spaced six feet apart in every direction.

On Sunday afternoon, the models arrived. Casting the show had been tricky. Earlier this year, many New York models who had European work visas relocated for the summer. “New York is the least desirable place to be right now for a model in terms of available jobs,” said Rachel Chandler, the casting director.

After sitting for hair and makeup — the hair stylists wore masks, but the makeup artists wore face shields — the models moved to their large shared dressing room, where their outfits hung on individual racks sandwiched between thick plexiglass panels. During rehearsal, they wore masks, though they needed to be reminded to spread out.

The six-feet-apart rule was a complicated policy. No one working backstage at a fashion show can really do their job without coming into close contact with another person. All they could do was try to avoid it.

When the 36 guests arrived, they filled out a health questionnaire on their phones before having their temperatures taken. They were escorted to the freight elevators, where stickers on the floor told them where to stand, and then to the runway.

Despite their socially distant seating, the guests congregated, greeting each other somewhat awkwardly — it’s never immediately clear who’s up for a forearm bump and who’s not — and talking about how strange it was to be at a runway show again. Strange, but nice. Most agreed it was nice.

The show began on time. The first model was the actress Indya Moore, wearing a long and loose sleeveless orange dress with eyelet details around her calves. (Ms. Moore’s mother was in the audience.) Nine minutes later, it was over. The small audience cheered.

As Mr. Wu took his bow, he noticed something: When he walked down the runway, he could make eye contact with people — including friends and loved ones. This wasn’t normal. He was used to looking out at a mad sea of phones.

“I just felt connected,” he said the next day. “I can’t say that about every show.”