“Something is missing,” said Cynthia Erivo, the Tony-award winning actress, as she judiciously eyed her reflection in the airy studio of Chris Gelinas, a designer. She was wearing a dress adorned from one shoulder to the next with hundreds of ostrich feathers, some of which were shipped to California and hand dipped in a delightful lemon yellow dye.

This was two days ago, at a final fitting for two dresses for the Tonys — one she will wear on the red carpet and one she will wear for a special performance.

CreditHeather Sten for The New York Times CreditHeather Sten for The New York Times

On cue, Mr. Gelinas and Ade Samuel, her stylist, got to work. They tucked an inch of fabric here, took scissors to the feather lining there, and deepened the slit to reveal a part of Ms. Erivo’s tattoo, attempting to conjure the necessary allure and pizazz. At the suggestion to add more feathers the pair took to the ground, kneeling at the base of Ms. Erivo’s dress where the unfinished ends flirted with the studio’s hardwood floor.

“I have a love for ’40s vintage glamour,” said Ms. Erivo during the quiet frenzy happening around her, while Caleb, her Maltipoo, lounged on the brown leather chaise and Drake’s voice crooned in the background.

The look — including the ombré effect created by the delicate layering of the feathers to the hourglass silhouette — evoked the style of Josephine Baker, one of Ms. Erivo’s inspirations. Sitting atop Ms. Erivo’s shaved head was an accompanying headpiece by Gigi Burris made of the same plumage, in addition to turkey and goose feathers.


CreditHeather Sten for The New York Times

To say a lot has changed in the two years since Ms. Erivo and Mr. Gelinas collaborated on her last Tonys look, a gown inspired by Diana Ross, would be an understatement. Since her Tony win for her Broadway debut as Celie in “The Color Purple” in 2016, Ms. Erivo has made a transition to film, appearing in Drew Goddard’s “Bad Times at the El Royale” and Steve McQueen’s “Widows” last year. She has also just finished filming as Harriet Tubman in “Harriet.”

“I do feel like there is a moment happening right now for me,” Ms. Erivo said.

CreditHeather Sten for The New York Times

The looks — both play with white — aimed to celebrate serendipity, as well as “the purity of this new phase and this new era,” said Ms. Samuel, whose styled celebrities include Yara Shahidi and Michael B. Jordan. The Tonys are always about channeling glamour, but, she said, this year’s look is about introducing the world to a Cynthia Erivo who knows she is “on the precipice of something astounding.”

CreditHeather Sten for The New York Times

Halfway through the fitting, when Caleb has fallen asleep and Ms. Erivo has finished her phone calls, including one to her best friend in London, Ms. Samuel and Mr. Gelinas tried affixing the feathers to the slit. Mr. Gelinas animated the string of feathers with delicate twists and with the help of Ms. Samuel held it up for Ms. Erivo’s approval. The feathers fluttered with Ms. Erivo’s every move as she posed in front of the mirror.

“Now, we have a dress,” she said, and smiled. “Onto to the next, people.”

“What I love about Cynthia is that she doesn’t just have opinions, she has a real vision,” said Mr. Gelinas. He described their relationship like working with a sibling — throughout the process they texted every other day and, because she was shooting a film, conducted the first fitting over FaceTime.

CreditHeather Sten for The New York Times

For the second dress, which Ms. Erivo will wear during her performance, Mr. Gelinas pleated the material, which has the texture of tweed with a bit more structure and flexibility, to the back of the gown, creating a halo effect. “I feel like I can add engineering to my resume after this,” he said, adjusting the voluminous piece.

“This is gorgeous,” said Ms. Erivo, as she twirled in the mirror. “That has to be where it starts: Am I going to feel good in this, whether or not people like it? If the answer is yes, then it’s probably the right thing to wear.”

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