It’s the end of the line for Danny and Don.

Don Winslow’s latest novel, “City in Ruins,” the final installment in the Danny Ryan series, will be his last. After 25 novels — seven New York Times bestsellers — Don Winslow is calling it quits.

In April 2022, Winslow announced that with the completion of the Danny Ryan trilogy, he would be turning his attention from the highly popular crime novels that have earned him fans around the world to the political arena. “It feels like my time and energy are better spent in that fight right now,” he said.

Winslow was in a reflective mood when I had lunch with him at Quecho, a Mexican restaurant in Julian, the small mountain town in the eastern part of San Diego County where he has lived for 26 years.

“I’ve had such a bigger and better career than I ever dreamed of — or probably deserved,” Winslow said. “But I remember back when it wasn’t that way.”

Throughout much of Winslow’s career as a writer, he had to work two or three jobs to make ends meet. He worked for many years as a private detective, served as a photographic safari guide in Kenya and directed summer theater in Oxford, England, to name a few. Although many of these adventures never made their way into his crime stories, they helped him grow as a writer. For example, he said that working in the bush as a safari guide taught him the importance of “seeing things in detail,” but it was often a struggle to get people to pay attention to his work.

“I remember driving up to Laguna Beach,” Winslow recalled, “to go to a bookstore for a book that was set in Laguna Beach. I was supposed to be there for two hours. Nobody came. An hour in, the bookstore owner asked me to lock up and she left!”

Many writers have experiences like this when they are starting out, but Winslow was no longer a novice. After 15 books, widespread attention and acclaim remained out of reach. Even when his surf-noir novel “Savages” was adapted by Oliver Stone, it underperformed at the box office.

“I got told so often what I wasn’t, that I almost forgot what I was,” Winslow recalled. “I was told you’re not a bestselling writer. You’re not an airport author. You’re a cult author.”

Winslow’s reputation as a crime writer’s crime writer changed when he started working with writer, producer and literary agent Shane Salerno at the Story Factory. A string of bestsellers followed, including “The Cartel” and “The Border” from a series of books about the Mexican drug war that featured DEA agent Art Keller. Then came “City on Fire” in 2022 and “City of Dreams” in 2023 from the Danny Ryan series.

“Don is a true artist who wrote books in a beautiful, economic, clean prose style that should be taught in Writing 101,” said Adrian McKinty, the New York Times bestselling author of “The Island” and “The Chain” who also works with Salerno. “Don told his stories in his way and never compromised his ideals or his vision to sell books. But sell books he did. By holding true to his principles and producing gem after gem, he let the audience build and come to him.”

Although Winslow is concluding his long career with “City in Ruins,” the gangster Danny Ryan has been on his mind for a long time.

“I wrote that first sentence of that first book 30 years ago and it hasn’t changed by a syllable,” Winslow said. “And the opening scene hasn’t changed very much at all. I always had this image of this guy laying on that beach, and it’s a beach I’m on every afternoon for six months of the year. I grew up on that beach.”

The saga of Danny Ryan and his rise from small-time leg-breaker to Hollywood mogul parallels Virgil’s “The Aeneid.” The woman who appears on that beach and kicks off a gang war between the Irish and Italian mobs in Providence, R.I., represents Helen of Troy. Danny’s journey to Hollywood, Winslow explained, echoes Aeneas’ journey to Carthage.

“There’s an incident in ‘The Aeneid’ quite early on where Aeneas is shipwrecked at Carthage, and he walks into a cave. He sees murals of the Trojan War, paintings of his dead friends, his home, all of that is right there on the wall. What could the equivalent of that be? And then it became very obvious: it’s film.”

In “City in Ruins,” the parallels continue when Winslow’s headstrong hero finds himself in Las Vegas. For someone trying to go straight and leave the violence of his gangster past behind him, it’s a curious choice for a new beginning. That’s the charm of Danny Ryan. He’s never the smartest or strongest player in the room. He’s stubborn and loyal to a fault.

“Classically, the definition of a hero in literary terms is he has to have a fatal flaw,” Winslow explained. “The Achilles heel with Danny is loyalty. I get that having grown up in Rhode Island, which is a tiny state with a little bit of a chip on its shoulder. I grew up playing pond hockey and if somebody dropped the gloves on your friend, you dropped the gloves. You didn’t think about who’s right, who’s wrong, you just did it. So I think there’s a lot of that in Danny that leads him to some bad, even dumb decisions.”

Although it takes a while for Danny’s past to catch up with him, “City of Ruins” provides an explosive finish to the trilogy, and is an instant classic in the lexicon of Las Vegas gangster fiction. But it didn’t come easy. Thirty years in the making, Winslow still hadn’t figured out the ending when the first installment was published.

“The chronology was problematic,” Winslow admitted, “but I was very interested in starting the trilogy so that it ended up in Vegas as the mob was fading out and corporate America was taking over.”

Tod Goldberg, New York Times bestselling author of the “Gangsterland” series set in Las Vegas, was already a fan of Winslow, but thinks his most recent work will cement his reputation.

“It’s this last ‘City’ trilogy of mob novels that I think will change the way history views Don,” Goldberg said. “He’s not merely a great crime writer, he’s one of the finest chroniclers of this twisted American life, where we are defined not by the good guys, but by who got away with it.”

After working so hard to achieve the success that eluded him for so long, is this really the end of Winslow’s writing career?

Well, yes and no.

“I think I’m done publishing novels,” Winslow said, “but there’s a lot of research I want to do. There’s things I want to learn about. I’ll probably always write, but I’ve made this decision about publishing and it’s pretty firm.”

In addition to the political videos that he creates and shares on his social media accounts, many adaptations of his books are currently in development. “City on Fire,” for example, is getting a movie starring Austin Butler. Winslow and Butler are among the producers on the Sony pic. He will always be a storyteller — Winslow says every one of his novels has been either sold or optioned by Hollywood — just in different media.

Still, Winslow’s exit leaves a massive hole. “It’s a huge loss to the crime writing community,” McKinty said. “For me, Don Winslow and James Ellroy are the two greatest American crime novelists of the last 30 years. His legacy is a tremendous body of work that any novelist would be proud of and the certainty that he took American fiction into extraordinary places that it would never have gone but for him.”

Lou Berney, award-winning author of “November Road” and “Dark Ride,” echoes these sentiments. “Don’s retirement from the crime writing community is a gut punch. He’s been such an inspiration to so many writers for such a long time. Every time a new Don Winslow book comes out, it’s a sharp reminder of how good, and how important, crime fiction can be. That’s irreplaceable.”

Winslow, who estimates that he’s spent more time with his fictional characters than actual human beings, is more sanguine about stepping away.

“I don’t want to push it, and I mean it,” Winslow said. “I want to be grateful for where I’ve come and let it go.”

Winslow will be discussing the book during Live Talks Los Angeles on April 11 at 8 p.m. at Moss Theater in Santa Monica.

Ruland is the author of “Corporate Rock Sucks: The Rise and Fall of SST Records” and “Make It Stop.”