PARIS.- This is a season of firsts for Dominic Sessa — a wondrous Cinderella moment on the threshold of further adventures in fame. Not yet two weeks out from the Golden Globes, when the 21-year-old actor sauntered onto the red carpet — tousle-haired in a Saint Laurent suit, his black silk shirt unbuttoned, his eyes hidden behind dark shades — unleashing a million online stans, he arrived in Paris for his first time at the fashion shows.

It has been a virtual eye blink since Sessa was in Santa Monica, California, to receive the Critics Choice Award for best young actor or actress, quickly followed by a BAFTA nomination in the best supporting actor category for his film debut in “The Holdovers,” director Alexander Payne’s darkly funny period drama set at a New England boarding school in the 1970s.

Here he is now in the opulent breakfast room of the Hôtel de Crillon, his gangly frame clad in sweats, wedged into a gilded Louis XVI chair, shyly requesting a glass of water. “I’m not a caffeine person,” Sessa said.

Neither is he a hypebeast. He has no public relations team or, for that matter, much presence on social media and so is all but oblivious of the effect he is already having online. The night of the Golden Globes, a single tweet on X, formerly Twitter, (“dominic sessa stop. your bob dylan drip is too immaculate. your timeless beauty swag is too unreal. timothee chalamet is gonna kill you”) was seen more than 1 million times in just hours.

Few who saw Sessa’s performance as Angus Tully, a troubled student abandoned by his parents over the Christmas holidays and forced to “hold over” at his all-boys prep school, would have been surprised to hear his name when the Oscars nominations were announced Tuesday. So natural is he in the role that it is a surprise to learn he almost didn’t get it.

“Until we actually started filming, Alexander wasn’t convinced, but they kept calling me back for auditions, and I really owe a lot of thanks for that to Susan and Paul,” Sessa said, referring to casting director Susan Shopmaker and his co-star Paul Giamatti, both of whom saw something in him he barely saw himself.

That Sessa became an actor at all was itself something of a fluke. A femur broken in a skateboarding accident during his time at the exclusive Deerfield Academy in Massachusetts, which he attended as a scholarship student, put an end to any ambition he had to play college hockey.

Sidelined by his injury, Sessa drifted into drama classes because, as he said, “I needed something to do.” While his natural talent is clear in “The Holdovers,” there is nothing about his profession, he explained, that felt to him inevitable.

“I’ve always been a very driven person, but until I got into acting, I had no idea what direction I was going to go,” he said. He allowed himself a wry smile and added, “Even now I have a major case of impostor syndrome.”

He also retains the wonder of someone who seems, at least for now, remarkably unaffected by the fizz of sudden fame. Arriving in Paris with a buddy from the “Holdovers” production company, Sessa largely chose to bypass the round of fizzy fashion week dinners and parties and did as most first-time tourists in Paris do: “We went to the Eiffel Tower.”

He and his buddy photo-bombed the Arc de Triomphe and put out feelers to everyone they encountered for tips on where real Parisians go to drink. Before heading back to Manhattan the next day, Sessa said, he hoped to use some of the spending money he brought with him to buy an Hermès scarf for his mother, a schoolteacher.

First, though, he would fold himself into a front-row seat at the Hermès menswear show alongside Daniel Radcliffe, James Marsden and Ramy Youssef, dressed for the occasion in a caramel leather jacket and printed patchwork cashmere sweater from the venerable luxury house’s fall 2023 collection, paired with his own rumpled Levi’s and some well-worn AM318 sneakers.

“I’ve never seen so many well-dressed people in my life,” said Sessa, who in his very short time in the public eye has already enraptured not only the internet but designers at top fashion houses. Thus far on the red carpet circuit Saint Laurent, Tom Ford and Celine have dressed the lanky actor, seeing in him the ideal embodiment of brand cool.

“I didn’t know how it worked at all,” Sessa said of celebrity dressing — in strategic terms, a wardrobing “Game of Thrones.” “I never really felt like I looked good before, so initially I was just grateful to the brands for allowing me to wear their clothes.”

His stylist, Warren Alfie Baker, who has helped craft the images of Andrew Garfield, Matt Bomer and Lucas Hedges, quickly set him right about that. Brands fork over plenty to put their designs on cool young stars. Many performers are, in fact, so extensively subsidized that they command high fees for wearing individual labels to, let us say, the Governors Awards before the Oscars preshow, the telecast, the Governors Ball afterward and the relentless round of after parties, including Vanity Fair’s annual circus, and exclusive satellite wingdings, the red carpet coverage of which is increasingly the sole point of these events.

“If I can bring sideburns back, that would be cool,” Sessa recently told Dazed Digital. And, as the internet frenzy surrounding his signature side whiskers suggests, the reluctant influencer has barely hit the start button on his fashion influence.

This article originally appeared in The New York Times.