Billy Porter is likely to sweep onto the Oscars red carpet on Sunday night, dazzling in a mélange of gilded feathers and a bouffant skirt, a pair of gold wings affixed to his head. It is all a bit extra, but he likes it that way, his tastes in tune with those of his stylist.

That would be Sam Ratelle, who can be spotted at similar high-wattage events, hovering phantom-like behind the scenes, tweaking a collar or wayward seam, making sure that no random wardrobe malfunction will dim his client’s luster.

Mr. Ratelle, as some will recall, is the man who tricked out Mr. Porter, the “Pose” star, for the Met gala last year in a blindingly jeweled cat suit that sprouted 10-foot wings; and who masked his client’s features at the Grammys behind crystalline fringe rigged to part like a curtain for a surprise reveal.

Will Mr. Ratelle top himself at the Oscars? Count on it. “What’s the red carpet if not theater?” he said.

There was not much hint in his youth that show business would become his métier. Mr. Ratelle, 31, arrived in this country from Honduras at the age of 8, the product of a punishingly austere religious upbringing, he said, that allowed him little access to outsiders, to say nothing of the magazines, TV shows and other pop totems of the day,

For him, the church, a Christian revivalist denomination called Branhamism, was an insulating fortress. Years later, after reading about Scientology, he said, “I realized I had been brought up in a cult.”

He was relaxing late last month, just days before the Grammys, at the apartment he shares with Ryan Ratelle, his business partner and husband of four years. Propped against a sofa tinted in a soothing shade of green, he was a picture of serenity, nothing in his look or manner suggesting the kind of flash you would expect from a red carpet Svengali.

He spoke candidly about an emotionally freighted boyhood, interrupting himself from time to time to field calls or intercept garment bags arriving for a photo shoot. “I grew up speaking Creole, singing Negro spirituals in a third-world country as a little Latino boy brought up by white missionaries,” he said.

Add to that mix a father with a taste for Rolex watches, and a mother who turned her back on life’s little luxuries in keeping with the strictures of her faith, and you have the makings of a seriously conflicted youth.

Did it help that his father took young Sam to strip clubs on weekend nights? Probably not. Mr. Ratelle spent the rest of the week with his mother, governed by an unremitting schedule of nightly church services and entire Sundays confined to a pew.

He found a solace, and inspiration, poring in secret over the fashion magazines he paid for by forging his mother’s checks. When his father gave him a computer, he found another escape, scouring the internet for dates.

“Even as a child, I had an innate feeling that there is something prepared for me in this world,” he said. “That’s what keeps you going.”

There were hurdles, of course. At 8, Mr. Ratelle moved with his mother to Miami and, eventually, to Houston, where church attendance remained central to his life. He bridled at the rituals. “I would say, ‘No, I don’t feel like washing that person’s feet during communion.’”

“I didn’t understand why, it was just an awful feeling I had being in that church, that there was something wrong with me,” he said. He winced recalling his mother’s reaction when she learned he was gay.

“She told me, ‘You have to leave,’” he said. “I remember coming home in the rain one day and finding all of my things on the front lawn.” He was in his late teens at the time.

To this day, he said, his mother has no clue what her son does for a living. “The idea of me putting a black man in a dress and having him prance around the world like that. … To her, that would be blasphemy.”

At 18, he bolted, finding temporary refuge in the Manhattan apartment of a boyfriend, and in a series of jobs that included a public relations stint at Club Monaco and, later, posts as a personal dresser at Saks and Bergdorf Goodman.

The work was intriguing, he said, “but I couldn’t see doing it for the rest of my life.” For several years he has been developing a musical, “The New City,” based on his childhood.

A couple of years ago, he was introduced to Mr. Porter, bonding with the entertainer through a shared affinity for musical theater, gospel music and R&B, and a predilection for the outré.

“Sam is a dreamer and has big vision,” Mr. Porter said. “I am a dreamer, and I have big vision. That’s why we connect.”

Mr. Porter recalled that their mutual fascination with the veiled Versace hat Billie Eilish wore to the American Music Awards in November spurred Mr. Ratelle to come up with the effusively fringed topper Mr. Porter wore at the Grammys.

Last year, when the star suggested wearing a bouffant skirt to the Oscars, Mr. Ratelle, who estimates that they have worked as a team on 150 red carpet looks, didn’t blink. His client, he knows, can rock a ball gown or bowler with equal flair.

“I thought, ‘Why not?’” Mr. Ratelle said, and went on to confect an explosive Christian Siriano fusion of tuxedo jacket and ultra-puffy gown.

Moving forward, Mr. Porter’s choices may be a shade more rarefied — and restrained.

“I’m finding a little joy in simplicity these days,” Mr. Ratelle said, a mood that on Sunday will be reflected in an Oscars gown that’s an unexpected marriage of frivolity and refinement, and in the relatively streamlined trousers and marabou-trimmed cape he plans to wear to the post-awards festivities, a look practically worthy of Jacqueline de Ribes.

It does take a certain chutzpah to put a man in a dress. Mr. Ratelle views the gesture as political, a visual retort to overly codified distinctions between masculine and feminine dressing.

“I think of myself as an activist,” he said. “I may not be able to go all over the world, heal people, preach to them or give them food. But I can make a difference — even if it’s just to make you smile.”