The new drama, which follows a gay romance over several decades, is the first TV series created by the Oscar-winning writer of “Philadelphia.”Ron Nyswaner, the Oscar- and Emmy-nominated screenwriter, can still recall a chance meeting on a beach more than 50 years ago. Then a teenager and a self-described “Jesus freak,” he’d come to Ocean City, N.J., to attend a Youth for Christ conference. Late one night, he said, while walking alone, he saw “a gorgeous, muscular guy” across the sand.That young man asked him to speak in tongues — it was an invitation to religious ecstasy and nothing more. Nyswaner complied. He told me this story over lunch in Manhattan’s Soho neighborhood, on a stormy afternoon in September, as a way to explain that, for him, “sex and the sacred have always been united.”He wanted that same union for “Fellow Travelers,” a new series that premieres Friday on Paramount+ and then on Showtime on Sunday.Moving back and forth from the early 1950s to the late ’80s, “Fellow Travelers,” based on the 2007 novel of the same name by Thomas Mallon, is a précis of 20th-century queer history viewed through a turbulent relationship between two men. Matt Bomer (“White Collar,” “Magic Mike”) stars as Hawkins Fuller, Hawk to his intimates, a State Department employee. Jonathan Bailey (“Bridgerton”) plays Tim Laughlin, a milk-drinking, God-loving naïf who dreams of working for Senator Joseph McCarthy.As they tumble through the decades — in and out of bed, in and out of love — the lavender scare, the gay liberation movement and the AIDS crisis happen around and through them.In “Fellow Travelers,” Jonathan Bailey, left, and Matt Bomer play men who move in and out of one another’s lives as history unfolds around them.Ben Mark Holzberg/ShowtimeNyswaner, who was dressed in all black save for a tan raincoat, claims to dislike love stories. “Yuck!” he said. (The two chunky rings he wore, mementos of former relationships, may have belied this.) But his genius resides in making the political feel shockingly intimate. Despite its many congressional hearings, “Fellow Travelers” is a love story, one illustrated with some of television’s most screen-fogging queer sex scenes. The first time Nyswaner read the novel, he fell in love with Tim and Hawk. It was that love — sexual, sacred — that inspired him to make the series, the first he has created for television.Nyswaner, 67, grew up in small-town Pennsylvania. Gay and closeted, he was an outsider as a child, an observer. That, he believes, is what made him a writer. After graduating from the University of Pittsburgh, he enrolled in Columbia’s film school. While still a student there, he slipped a script to the director Jonathan Demme. Demme optioned it, and Nyswaner has supported himself as a writer ever since.His first major success came in 1993 with “Philadelphia,” directed by Demme, the story of Andrew Beckett (Tom Hanks), a lawyer who believes he has been wrongfully terminated by his firm because of his AIDS diagnosis. (Nyswaner, whose script earned him an Oscar nomination, makes a cameo in a party scene dressed as a priest.)By that time, Nyswaner was in the throes of drug and alcohol addiction. In the five years after the film’s release, newly flush with fame and cash, his addiction worsened.“I dedicated myself to cocaine and alcohol and sex, with tragic results,” he said. (He details this tragedy, which involves the suicide of a sex worker, in his 2004 memoir, “Blue Days, Black Nights.”)There was heat on him in Hollywood then. But he showed up to more than one meeting high on methamphetamines, and the heat dissipated. Which didn’t especially bother him. Having found success early, he has rarely been swayed by the demands of the market.“I always just wanted to write what I wanted,” he said.“The best thing you can do with any marginalized character is to make them as fully human and complicated as every other straight character that’s out there in the world,” Nyswaner said.Erik Tanner for The New York TimesNewly sober, he proved this. He scripted the 2003 true-crime Showtime film “Soldier’s Girl,” about an Army private’s relationship with a transgender cabaret performer, and followed that with the 2006 adaptation of W. Somerset Maugham’s doomed romance, “The Painted Veil.” Neither was intended for mainstream success, but these works had the heartbreak he loved, the passionate intensity.In 2012, his management team asked him what he wanted to do next. “Get me out of my house,” he told them. He had spent two decades living in upstate New York. Now, he found himself craving the crush of a big city and the camaraderie of a writers’ room. Though he had already optioned “Fellow Travelers,” he back-burnered it in favor of moving to Los Angeles and joining two Showtime series: first the punchy noir “Ray Donovan,” and then “Homeland,” the fervid espionage thriller. In 2018, when his time on “Homeland” ended, he felt ready to turn to “Fellow Travelers.”In “Fellow Travelers,” Nyswaner expands on the themes that define much of his film work — the ways in which longing, sex and secrets intersect with the law. In the series, the historical characters and events are meticulously researched. (There are perhaps a few aesthetic lapses — did men really work out this much in the 1950s?) But Nyswaner wanted to offer something more than a history lesson. Hawk and Tim and the show’s other queer characters are intimately involved in this history, and they are not mere bystanders and victims. Occasionally, they are aggressors.“The best thing you can do with any marginalized character is to make them as fully human and complicated as every other straight character that’s out there in the world,” he said.Many of those complications are revealed in the sex scenes. Thirty years ago, “Philadelphia” received criticism for shying away from gay sexuality. “Fellow Travelers” is not so shy. “Perhaps I overcompensated,” he said, laughing.Nyswaner said each sex scene was intended to move the story forward and dramatize a power exchange.ShowtimeNyswaner, who has something of the provocateur in him, described a scene late in the series, a threesome that leads to a nervous breakdown, as “very much me” and “one of my proudest achievements.” (For that scene he educated the director on the uses of amyl nitrate.)If these scenes are not especially graphic, they are unusually specific in their mapping of power and desire. Nyswaner had rules for these scenes, which were carefully choreographed and scripted. Each had to move the story forward. Each had to dramatize a power exchange. And no act could be repeated, which invited creativity in the later episodes.The queer characters are all played by actors who openly identify as queer. “It wasn’t a requirement, but it was certainly a strong motivator for us,” Nyswaner said. He believes the casting may have contributed to the veracity and intensity of these scenes.“I do think it might have really made a difference and made everybody more comfortable,” he said.Nyswaner isn’t sure if writing about gay characters is a path that he chose for himself or one that the success of “Philadelphia” forged for him. Either way he is glad to walk it.“I so love, love, love being a gay man,” he told me over lunch. “I enjoy being slightly to the side of everything.” He worries, of course, for the state of L.G.B.T.Q. rights, but he has always enjoyed this feeling of being an outsider. “Outlaw” was another term he used.He isn’t dating anyone just now. His preference, he said, is for “unsuitable men, some of them are quite delicious.” Colleagues keep encouraging him to download a dating app, but so far he has resisted. These past few years, his primary relationship has been with Tim and Hawk, the characters he fell for a decade ago.“I wanted to live within that relationship,” he said. “And I have.” More