After 9,000 or so bylines, Pete Hamill has probably earned the opportunity to write the lead of his own profile.

“Oh, I thought about it,” Mr. Hamill said on a recent Friday morning, hunched over a walker in the kitchen of his brownstone apartment in the Prospect Heights neighborhood of Brooklyn.

“‘Pete Hamill is 84,’” he said. “‘He’s got stents in his heart’— I do, I have four. ‘He’s got two broken hips. He has to go to dialysis three times a week. He’s even got a pacemaker.’”

“‘But,’” he added, “‘he ain’t done yet.’”

Mr. Hamill was a star city columnist when such a thing was still possible. His gritty yet soaring dispatches about cops, immigrants and crooked City Hall cronies earned him a reputation as a tabloid poet, long before the word “tabloid” was synonymous with celebrity fluff.

Even so, he never let the tabloids contain him. Mr. Hamill wrote acclaimed novels and mingled with movie stars. He interviewed legends of the 20th century like Dr. Martin Luther King Jr. and Che Guevara, and palled around with Robert F. Kennedy.

All of that makes Mr. Hamill a living archetype of a dying breed, the celebrity newspaperman — famous enough that in 1977, Jimmy Breslin, his friend and fellow columnist at The New York Daily News, outed him for dating Jackie Onassis.

Mr. Hamill rolls his eyes at such talk. He has no time for Hollywood, or legacy. Three years ago, he moved back to his native Brooklyn with his wife, Fukiko Aoki, and is now locked in a battle with his aging body to finish his 22nd and, he said, possibly last book, “Back to the Old Country,” a reminiscence about the borough that shaped him.

“I grew up with what I call the ‘Tenement Commandments,’” he said, dressed comfortably in black track pants and a sweatshirt. “One of them was, ‘Remember where you’re from.’”

‘Extra Innings’

There may be another reason for his look back.

In 2014, Mr. Hamill, then 79 and living in a TriBeCa loft, was feeling profoundly weak and tired, and was rushed to a hospital, where doctors discovered that he was in the first stages of kidney failure.

On his third day in the hospital, he was in cardiac arrest. Doctors also found mysterious fractures of his pelvis and spine. Heavily medicated, he slipped into a medical coma, and remained there for nine days. Doctors told his wife he would never emerge.

He emerged.

In fact, he emerged in unusual fashion. “When I came out of it, I started talking in Spanish,” Mr. Hamill said. (He lived in Mexico as a young man, studying art on the G.I. Bill.)

He also emerged with a mission: to return to Brooklyn after nearly 30 years. The place he landed sits some 20 blocks from the tenement where Mr. Hamill grew up in what is now known as South Slope.

With its period moldings and overflowing bookcases, the parlor duplex is more cozy than opulent — a home for a writer, or rather, two. (Ms. Aoki, whom he married in 1987, is a former bureau chief for Newsweek Japan and the author of 15 books.)

The book he spends his days writing is not a memoir, precisely. He’s already done one of those.

“A Drinking Life,” from 1994, recounted his childhood of stickball and street fights as the eldest of seven children of Catholic parents from Belfast, Northern Ireland; his rise from Brooklyn Eagle delivery boy to newspaper columnist; and his boozy nights at old writers’ bars like the Lion’s Head in Greenwich Village, which led to a messy breakup with alcohol. He quit cold turkey on New Year’s Eve, 1972.

“I didn’t want to be an Irish stereotype,” he said.

His current book is a rumination on the Brooklyn of his youth: Prospect Park, Coney Island, Sunset Park and “explaining the notion of home,” he said. It is “trying to make sense of a life” now that he has moved into “a period of extra innings.”

“It’s just looking and inhaling and remembering, which is, as you get older, harder because you don’t remember the new,” he said, seated in a white sofa in his living room, which was filled with family photos and music CDs. “I can remember things from 1943, and sometimes not remember what the hell I had for breakfast.”

No longer is Mr. Hamill the burly tough guy with the mournful eyes who had the rugged good looks of a television homicide detective. He is thinner now, decades of deadline stress etched into the lines of his face. He moves haltingly. His wife informed me that he would probably only have the energy for one hourlong interviews at a time.

Even so, Mr. Hamill seemed anything but defeated. Rather than sinking into the sofa, he perched on its edge, leaning into the conversation. He recounted his tales with energy and wit, his eyes bright as he tried to craft the perfect pull quote.

If memory sometimes fails him, maybe it is because there is too much to remember. Legacy has been a major issue in Mr. Hamill’s life of late, especially after the recent HBO documentary, “Breslin and Hamill: Deadline Artists,” which profiled Mr. Hamill and Jimmy Breslin — two Irish outer-borough guys who became kings of the city, back when New Yorkers still announced who they were by the newspapers they read.

The film is a celebration of an era both very recent and very lost, when the overflowing ashtray was as much a part of the newsroom landscape as the Royal manual typewriter, and Mr. Hamill and Mr. Breslin helped define the stories that defined New York.

Brawler and Bard

The two were friends, but opposites. Mr. Breslin was grandstanding, pugnacious, in love with the very idea of Jimmy Breslin. Mr. Hamill — big-hearted, self-effacing, in love with the rhythms of the city and the poetry he found there.

Even his moral outrage carried a hint of lyricism. In 1989, when Donald Trump took out full-page ads in city newspapers calling for New York State to adopt the death penalty following the arrest of the Central Park Five, the African-American and Latino teenagers accused — wrongfully, it turned out — the raping of Trisha Meili, the so-called Central Park Jogger, Mr. Hamill fired back:

“Snarling and heartless and fraudulently tough, insisting on the virtues of stupidity, it was the epitome of blind negation,” he wrote in Esquire. “Hate was just another luxury.”

In his columns, Mr. Hamill mastered an almost haiku-like brevity. “Tabloid stories are highlight films,” he said.

But he also knew how to spread his wings. As a magazine writer for Esquire and New York Magazine, he rode the wave of New Journalism alongside Gay Talese, Gloria Steinem and Tom Wolfe (all of whom share recollections in “Deadline Artists”).

Mr. Hamill’s 1969 article, “The Revolt of the White Lower Middle Class,” could have been written in 2016: “The working-class white man is actually in revolt against taxes, joyless work, the double standards and short memories of professional politicians, hypocrisy and what he considers the debasement of the American dream.”

“Any politician who leaves that white man out of the political equation,” he added, “does so at very large risk.”

Mr. Hamill’s writing was so New York that you could almost hear the subway rattling behind every sentence. But he never let the city constrict him. He filed dispatches from Belfast at the height of the sectarian Troubles, and from the battlefields of Vietnam.

His intimate interview in Rolling Stone with John Lennon in 1975 has entered into Beatles lore, although the two got off to a rocky start. “I hated him,” Mr. Hamill said.

The trouble started when Mr. Hamill found himself seated with the members of the Beatles and the Rolling Stones at a large table at a London club called the Ad Lib. The two almost came to blows when Lennon suggested that Yanks were not welcome.

“Why don’t you just get the hell out of here,” Lennon said.

“Why don’t you make me?” Mr. Hamill replied.

As Mr. Hamill recounted in the 1980 New York Magazine article, “The Death and Life of John Lennon”:“He stared at me, and I stared back. The Irish of Liverpool challenging the Irish of Brooklyn. The music pounded, and then, as if he had seen something that he recognized, he smiled and broke the stare and peered into the bottom of his glass.”

Robert F. Kennedy was more than a subject. He was a friend, despite the fact that Kennedy, the scion, and Hamill, the tenement son, represented opposite ends of the Irish-American experience.

Kennedy used to tag along with Mr. Hamill to blue-collar bars in Brooklyn to talk to constituents. And Mr. Hamill was only feet away when the senator was mortally wounded at the Ambassador Hotel in 1968. “I could see him blinking,” Mr. Hamill said. “He didn’t utter a word.”

It would not be his last encounter with the Kennedy clan. A decade later, he found himself dating one of the most famous women in the world, Jacqueline Kennedy Onassis.

No Time for Twitter

The HBO documentary dug deep into his relationships with famous women: he lived with Shirley MacLaine in Brooklyn; he brought Linda Ronstadt to Thanksgiving dinner at his sisters’; he almost clocked Ron Galella, the ur-paparazzo who hounded Mrs. Onassis for years.

But it is a topic that Mr. Hamill is loathe to discuss. “I really agree with García Márquez, who said once, that everybody’s got three lives: public life, private life and a secret life,” Mr. Hamill said in the HBO film. “Private life is by invitation only. Secret life is nobody’s business.”

To him, the focus on his boldface paramours damaged the film. “They spent more time on Jackie Onassis and Shirley MacLaine than on my wife, and I’ve had my wife for 35 years,” he said. “I don’t want her feelings hurt by stupidity from 40 years ago.”

Maybe that’s an old-fashioned view. It wouldn’t be his only one. Mr. Hamill is of a generation that believes that a man could learn to be a man by reading Hemingway. Last year, he published a new introduction to his 1998 book, “Why Sinatra Matters.”

Even so, he resists the idea of being an octogenarian wallowing in nostalgia, even if he did return to Kings County to write a book about lost Brooklyn. He is maybe halfway finished. Progress can be slow. “It’s hard to do legwork with two broken hips,” he said with a weary smile.

Legwork that day consisted of a brief house tour, with Mr. Hamill guiding his walker to get him through the kitchen to show off the large, and largely unfinished, yard in back.

“The house was built in the 1870s, and you can see what this must have been,” he said, surveying the backyards of the neighboring brownstones, which aside from a lack of clotheslines, looked much like they did in the days before the internet, or even television.

“See that tree there, the big, thick one a couple yards back,” he said, pointing toward a towering oak tree. “Imagine when that was a kid here, 100 years ago.”

If he squints, the new, cosmopolitan Brooklyn of Michelin-starred restaurants and glassy condominiums is not so different from the wartime Brooklyn he knew as a child. “Until a helicopter comes over, flying to the Hamptons,” he said.

Those are observations he will mine for the book. Some days, he is able to put in a full day writing. On dialysis days, he comes home drained. “I have to eat lunch — vitamin L — and take a nap before I begin to feel I’m able to do work. When I do, it’s late in the day.”

The news of the day brings its own form of distraction. “Every day, it’s another stupidity or tragedy,” he said. “To call Washington D.C. a moral pigsty would be an insult to pigs.”

At least he can avoid the time suck of social media that plagues younger journalists. His last tweet was sent in 2015.

“I don’t do Twitter,” he said. “I don’t do LinkedIn. I don’t have enough time.”

“And time,” he said, “is the most urgent four letter word when you’re my age.”