Barbara Scheiber has written a fictionalized semi-autobiographical account of her youth. Her father had an affair with his secretary, which happened to be captured and immortalized in a famous Walker Evans photo which hangs on the wall of her office, right. (Sarah L. Voisin/The Washington Post)

At first blush, the photograph seems to capture a scene of carefree affection: a couple enjoying a warm, breezy day at the amusement park on New York’s Coney Island. He looks older and is more formally attired; she seems younger and wears a clingy, backless dress. They are unaware of the camera trained on them from behind.

Who are they? They were not identified by the photographer, Walker Evans, a master of what’s known as anonymous street portraiture. His Depression-era, direct-on portraits are more famous, but Evans often shot people unobtrusively to capture unguarded moments. He took this picture in 1928.

The photo became the signature poster for an Evans show at the Metropolitan Museum of Art in 2000. Now, it illustrates the cover of Barbara Scheiber’s first novel, “We’ll Go to Coney Island,” published last month. The book consists of intertwined stories she wrote over the course of 20 years, slowly tweezing scenes and dialogue from her capacious memory and crafting immersive scenes inspired by growing up in a Jewish immigrant enclave of New York.

Scheiber, who lives in Gaithersburg, is 92 years old. She was 6 when Evans took that picture. Her life was irrevocably altered, she says, by the man and woman in the photograph, who surely would not have wanted to be identified at the time.

They are her father, Harry A. Gair, a lawyer, and his secretary, Harriet, his mistress, she says. They are on a clandestine date.

Barbara Scheiber’s father had an affair with his secretary, which happened to be captured and immortalized in this famous Walker Evans photo. (Walker Evans Archive, The Metropolitan Museum of Art/Handout)

“Thunderstruck” is how Scheiber describes her reaction to seeing the photo while leafing through the New York Review of Books about a decade ago. Although the image doesn’t capture the couple’s faces, she was certain it was them — easily recognizing her father as well as the woman who became her stepmother after Gair’s divorce from Scheiber’s mother, in the mid-1930s. “He is recognizable from any position, back or front,” she says. “The head is unmistakable, strikingly him.” And her? “It’s no question. It’s a gestalt. That’s her.”

Her brother agrees.

“The posture of both of them is unmistakable,” says Donald Gair, 89 and a practicing psychiatrist. “I think it is my father and stepmother. You see certain people all of your life who mean a lot to you, and you can recognize them.”

When she discovered the image, Barbara Scheiber felt like a voyeur, “as if I were actually seeing my father and his lover on their date, that I was, in fact, trespassing, invading their privacy,” she says. She still gets that feeling today.

“It’s such an amazing thing to have a picture like that thrown into your life, when you know you should not be looking,” the writer says. “It’s such a shock to me to see it still.”

To her, it is proof of what she felt at a young age, although proof wasn’t really necessary. As her book richly shows, there are things in childhood that burn into memory and stay there — like photographs, seen forever.

* * *

Barbara lives with her husband, Walter Scheiber, in an unremarkable ranch home adorned with placards supporting President Obama; a watercolor portrait of Franklin D. Roosevelt presides near the front door. Walter is also 92. They were born a day apart and have been married for 65 years. They offer bagels and lox, banana bread and a log fire to a visitor on an icy day.

Barbara is small but sturdy, unstooped. She remembers writing stories since childhood. She majored in drama at Vassar, and her career included working during World War II on the radio side of United Press, writing plays based on war reporters’ experiences.

In Washington later, she became an education advocate for children with disabilities, running a national information center and co-authoring a nonfiction book on learning disabilities and one on Williams Syndrome, a genetic disorder that can cause severe learning and health problems. (The youngest of the Scheibers’ four children has Williams Syndrome.)

Walter, the former city manager of Rockville, is taller, lean and taciturn or perhaps just not wanting to steer conversation away from his wife’s accomplishment. A bombardier in the war, he flew over Germany in B-24s. He won’t be coaxed to boast, saying, “It was just another job.”

Most aspiring authors without agents — people like Scheiber — are lucky to see their work published. But over the years, she has placed stories in small literary journals and picked up prizes. She also won the admiration of peers in the local writing workshops she started assiduously attending after retiring in the mid-1980s.

“We’ll Go to Coney Island” was put out by a small press and received no marketing. It is not the kind of book that gets reviews from critics in major publications — in fact, no one has reviewed it. But some who have read the novel call it exquisitely written and remarkable for its detail and insights into family life.

Roy Peter Clark, a writing expert with the Poynter Institute in Florida, praised the novel in a back-cover blurb — although he probably would never have seen the book except for a family connection: He is friends with the journalist Dave Scheiber, one of Barbara’s sons, and has met the author.

But Clark’s view stands. “The voice of the work feels so authentic to me,” he says in an interview. “She creates a world that I very much want to enter and experience myself.”

* * *

At the center of Barbara Scheiber’s autobiographical fiction is her father, represented in the book by a golden-tongued seducer named Aaron who escaped the New York tenements in the early 1900s to become a well-off lawyer. Scheiber’s father founded his firm in 1919 and became an acclaimed personal-injury attorney in Manhattan. Truly self-made, Harry Gair never finished high school, never went to college or law school but passed the bar by studying law himself.

“He was extraordinary,” his daughter says. She adored him.

Scheiber’s mother, Mollie, was exceptional in her own right, rising from the sweatshops of the Lower East Side to gain a master’s degree and career in psychological testing. The book imagines a fictional version the couple’s courtship and describes the painful dissolution of their marriage.

Minna, the character who stands in for Mollie, is consumed by resentment toward her ex-husband and his eventual second wife. That resentment cuts hotly through the novel — “honed, steely hate,” Scheiber writes.

Before the real-life divorce, the young Barbara sensed what was going on between her father and his secretary. “As a child, he took me to her apartment,” she says. “I knew they had a very close relationship, more than I should have known.”

A theme of torn loyalties binds the book. Children in such situations sometimes are forced to navigate parlous emotional waters, to keep secrets, to negotiate truces, to choose sides. Sitting in her living room, Scheiber talks quietly as she transits the decades. A long-ago history of hurts is still present.

“I was loyal to my father; I didn’t want to lose my father,” she says, “and I was loyal to my mother.

“I didn’t want my father to go off with another woman. But I also liked her.” For many years, Barbara maintained a “close relationship” with Harriet, she says.

“Those conflicts are so deep.”

She hopes the father in the book does not come off badly. “He was very guilty about all these things,” she says of her real father. “He was a complicated man who felt the weight of his own errors. But also felt the pleasures.”

Harry A. Gair died of cancer at 81 in 1975. Harriet E. Gair, who had started working for him at the age of 15, eventually became a lawyer and joined his firm. She died at 100 in 2006.

Their son, Tony Gair, a prominent New York lawyer, has skimmed Scheiber’s novel. “She is a great writer,” he says. “She is a brilliant woman.” But Scheiber never got over her parents’ divorce, he says.

What about the picture?

“It certainly looks like my father from the back,” Tony Gair says. “Whether it’s my mother or not, I have no idea.”

* * *

“Let me show you the poster,” Barbara Scheiber says, rising from her living room couch. It’s the one from the Evans exhibit at the Met. She keeps it in her writing study. With slight difficulty, she ferries the large framed reproduction back to the living room.

“Isn’t it beautiful?”

“The book was almost all done when I saw this picture,” she says. Part of it was already in the book — not the exact scene, but a certain sentiment, from the mistress’s point of view.

“What she’d longed for, never saying the words, was to show their love in daylight, in public,” Scheiber writes.

After she saw the photo, she could finally continue their story. She could, she says, describe a truth too disturbing for a young child to deal with. She would bring to life for readers in 2014 a secret moment between a man and woman on a boardwalk 86 years earlier.

It became her novel’s prologue:

“His arm slips around her waist. She lets her hand rest on his shoulder, exhaling slowly. What is there to be afraid of? His hand on her back says that they can risk whatever comes next and then next. He will make the story end safely.”