Julia Garner

Twenty-two years after his Costume Institute internship scored him a ticket to the Met Gala’s after party, Zac Posen decked out his celebrity female guests with 3-D designs.

Katie Holmes, Jourdan Dunn, Nina Dobrev, Gia Coppola and Deepika Padukone each wore sculptural 3-D garments or accessories designed by Zac Posen x GE Additive x Protolabs. They all descended on his East 54th Street offices Monday afternoon before boarding the 40-foot white party bus he chartered for them so they could remain standing en route to the Met. Posen said he aimed to show the boundlessness of creativity. “Did I ever think that I would be working on a Met Gala with plastics scientists and engineers that build jet engines? Never,” he said.

The designer teamed up with GE about a year ago and started the project by visiting a 3-D-printing facility in Pittsburgh. “We used a technique called SLA, which involves micro liquid layers of plastic — thinner than a piece of hair — that is layered on and guided by a laser that forms the shape that has been digitally rendered. That’s how you get the dimensions,” said Posen, noting how three petals take four to five days to layer and print. “As it’s printing, it’s curing with the lasers as well. The polymers are bonding together, which holds the form and the heat cures that. It’s pretty camp in its own way.”

Dunn’s rose gown featured 21 petals, averaging 20 inches and weighing a pound each. Finished with primer and color shifting automotive paint, the cage that fastens the petals was made of titanium. Dunn’s body mapping took a full hour, scanning every inch of her whole body. “This dress is made and molded for me. No one else can wear this but me,” she said. “That whole experience was surreal.” And instead of the usual crazy, hectic last-minute changes before the gala, this year has been “super-chilled,” Dunn said. “I’m just excited for everyone to see this amazing piece of art.”

Dobrev’s bustier required more than 200 hours of work, whereas Holmes’ palm leaf collar accessory was made of Accura 60 plastic and printed on a stereolithography machine. The bustier’s fragility required the help of five people just to put it on Dobrev. Having recently watched a documentary about robots, she said the fact that the garment was 3-D-printed is both the coolest and the scariest part of it. “The dress was basically made by a robot in a way. It was designed by Zac. Between him and the robot, it’s the most futuristic thing I’ve ever worn,” Dobrev said, unfazed by the machine-versus-man element. “Technology and life are going in that direction. Instead of fighting it, we should try to coexist in the best way to do it. There are certain things that you can and can’t do,” noting how the bustier required six weeks to be developed, including more than one week to be printed in Germany.

Garner donned a headpiece made of Nylon 12 plastic and printed on a Multi Jet Fusion machine, and Padukone wore a gown with 408 delicately printed 3-D embroidery. Posen, meanwhile, dressed up the velvet Brooks Brothers jacket (in an Oscar Wilde-inspired purple) that he planned to wear with 3-D cuff links. His dinner guests Andrew Garfield and Vito Schnabel had Brooks Brothers ensembles to wear, too.

Posen advised “Ozark” actress Garner, a rookie to the Met gala, to approach it like a performance in a show. “It’s almost easier for me. I’m portraying someone else. I’m not having anyone look at me. I wanted to walk like that on the subway every day,” she said. “We did a block rehearsal — the movement of a scene.”

Above the whir of a hair dryer, Garner said, “We’re New Yorkers. I grew up going to the Met. It’s not every day you go to the Met at night.”

Nearby, another first-timer, Coppola, was having her makeup done by Charlotte Tilbury. She and tablemate Garfield would have plenty to chat about. Coppola is directing and cowriting “Mainstream,” in which Garfield and Maya Hawke will headline. (The latter has modeled for Posen.)

As an 11-time guest, Dunn said everybody still gets nervous. “When you’re all lined up — amongst greatness — everyone is anxious and nervous. That feels a bit comforting, knowing that someone of that level is feeling the same thing that I’m feeling,” she said.