Julia Whelan climbed into the double-walled, foam-insulated booth in her home office near Palm Springs, Calif. In preparation, she had refrained from alcohol the night before, had avoided dairy since waking at 6 a.m. and had run through the humming and vocalizing of her warm-up exercises.

Her glass Ball jar filled with water, her Vaseline lip therapy at hand, she was ready to work. So was the man wielding the jackhammer in her backyard, a not-subtle reminder of what it means to be a victim of your own success.

Whelan, 38, is the soothing, assured female voice behind Gillian Flynn’s thriller “Gone Girl,” Tara Westover’s memoir “Educated” and more than 400 other audiobooks, as well as the narrated versions of many articles for New York, The New Yorker and other magazines. She has been so prolific that she and her husband splurged on a backyard remodel, which included blasting a hole in the ground for a swimming pool. The problem is that in her business, quiet is an occupational necessity. “I’m done trying to dodge noise,” she said, removing the “cans” (headphones) from her ears.

A former child actress, Whelan was 15 when she was cast in the ABC drama “Once and Again,” Edward Zwick and Marshall Herskovitz’s follow-up to “Thirtysomething.” Then as a 30-something herself, Whelan found she could more successfully blend personal happiness and professional achievement if she moved her performances from the stage to the page.

She has emerged as one of Audible’s most popular narrators, said Diana Dapito, the audio company’s head of consumer content. “You have a lot of driveway moments with Julia,” she said, meaning that you can’t turn off the car and stop listening, even once you’ve arrived home.

Taylor Jenkins Reid, the best-selling author of “Daisy Jones & the Six” and “Malibu Rising,” became friends with Whelan when she narrated Reid’s 2015 novel, “Maybe in Another Life.”

A few years later, when plans were underway for the audio version of her 2017 book “The Seven Husbands of Evelyn Hugo,” Reid let her publisher know that she wanted Whelan for one of the characters. She was told “don’t hold your breath,” that Whelan was so sought after that six months’ notice was required.

This delighted Reid. “Who doesn’t like to see their friends in such high demand?” she said. (Reid called in a favor and booked her friend to help narrate the book.)

The range of Whelan’s work is sweeping. Between bursts of construction, she recorded “pickup” for an article that would appear in The Atlantic. This means that she had already narrated the piece but was redoing a few sentences in which she had misread or mispronounced words, including one about Russia’s justification for invading Ukraine. “This was not genocide,” she said, and paused. “It was defense against genocide perpetrated by the Kyiv regime.”

Then she turned to the narration of a forthcoming book. It is a novel Whelan herself has written, “Thank You for Listening,” which is set in the audio industry and centers on a successful woman who lives her life mostly by voicing the words and experiences of others — that is, until she gets paired to read a famous romance novelist’s final book with Brock, an enigmatic male audiobook narrator.

“Question,” Whelan said into her microphone, speaking as Sewanee, her female protagonist, who is texting Brock. “Any interest in doing something other than romance? A friend is casting a Clancy-esque book and needs an alpha assassin sound.” She stopped the recording, hit rewind and reread a passage she garbled.

Her narrating voice, slightly different from her regular speech, is crisp and low-pitched. There is no singsong, no upspeak. Her narration is a raised eyebrow and a tilt of the head.

“I have an absolute voice crush on her,” said Olivia Nuzzi, New York magazine’s Washington correspondent whose work has been narrated by Whelan. “There is some Joan Didion quality to her voice, detached but not uninterested, with a conspiratorial tone that makes her a very compelling storyteller.”

‘Narrating a book really is a performance.’

Whelan wanted to write “Thank You for Listening,” due out from Avon on Aug. 2, because the heard-but-not-seen dynamics of audio is, she said, “perfect for rom-com material.”

It also was an opportunity to peek into the audiobook world. “It wasn’t until I got into the recording process that I realized just how meta the whole thing is,” she said.

As Whelan spoke, her tone shifted from conversational to controlled, from chatty to narration. “This is what happens when I get into storyteller-mode,” she said.

Once she has taken on a project, she reads through the book once or twice, deciding on themes to highlight when she gets into the recording booth by using different tones and accents, and emphasizing certain words. “Narrating a book really is a performance,” she said, “and it can be harder to do than acting, because I can’t use my eyes or a facial expressions to convey something to the audience.”

Whelan grew up in Salem, Ore., the daughter of a firefighter father who served in the Oregon House of Representatives for two years and a homemaker mother. They divorced when she was a teenager.

An only child, young Julia devoured books and lost herself in make believe. By the time she was five, she was acting in local theater productions.

She began to travel to Los Angeles. In 1999, she auditioned for the “Once and Again” creators Herskovitz and Zwick. After she did a reading as Grace Manning, the teenage daughter of a suburban Chicago divorced woman (played by Sela Ward), Zwick said they knew they had found their young actress. “We looked at each other and said, ‘Check that box: Done,’” he said.

“There are people who you meet at an early age who you know understand things that cannot be taught,” Zwick added, mentioning actors like Claire Danes and Evan Rachel Wood, whom he also worked with when they were children. “Julia is one of them.”

Whelan played Grace for three seasons until the show was canceled in 2002.

As a working child actress, Whelan had been primarily home-schooled and tutored, so when the show ended during her late teens, she decided to embrace a traditional educational experience. She attended Middlebury College in Vermont and spent her junior year in a study-abroad program at Oxford University.

Returning to Los Angeles in 2008 after a hoped-for Rhodes Scholarship didn’t pan out, she thought she would pick up her career as she had left it. She booked movie-of-the-week roles, a guest spot on shows including “NCIS” and “The Closer,” but the big auditions didn’t work out and she felt a lack of momentum.

At her Middlebury graduation, she had been approached by a friend’s mother who worked for Brilliance, an audio publisher. The woman told Whelan of the opportunities in the expanding medium of audiobooks. After a year back in Los Angeles, Whelan called the woman and said she’d like to give narrating a try.

‘Putting little curls on certain words.’

Whelan began taking on audio projects and got her big break in 2012 with “The Witness,” a best-selling novel by Nora Roberts. It was the first of more than five books (and counting) written by Roberts that Whelan would narrate.

A second breakthrough came when Whelan landed a gig to narrate the female main character of a thriller written by Flynn. The book was “Gone Girl.” After reading it, Whelan said, “I thought, ‘This book is going to be huge.’”

Flynn had been familiar with Whelan because she had been a fan of “Once and Again.” “There aren’t a lot of actors that I think could do Amy,” Flynn said, referring to the “Gone Girl” antiheroine Amy Dunne, particularly an audio-only version of her. “Julia has a way of putting little curls on certain words,” she said.

The book became a blockbuster, and the success of the audio version made Whelan start to take her side hustle more seriously.

Also in 2012, while she was filming a Hallmark movie, “The Confession,” her father died after suffering a heart attack, bringing on a period of grief and self-reflection.

Whelan was 27 and decided that she would give herself until she was 30 to find a firm career path. In 2014, just before the milestone birthday, she was cast in a pilot for a television series, but when it wasn’t picked up, she felt ready to change focus.

About five years ago, she became romantically involved with Geof Prysirr, who had been her acting coach and guardian when she was living in Los Angeles as a teenager. She is aware how that comes off. “It sounds more sensationalistic than it is,” she said. “This is a good man who kept me very safe in this ridiculous industry. And then I fell in love with him in my thirties.” They bought a house near Palm Springs and moved there full time. They married in 2018.

As she spent time subsuming herself in the writing of others, she began to think more about her own creative ambitions. She had been hired to rework an existing screenplay that was set at Oxford University. After that, at the suggestion of film producers, she went on to write a novel, “My Oxford Year,” about a Midwestern student on a Rhodes Scholarship. It was published in 2018.

That year she was also contacted by an entrepreneur who was working on a start-up called Audm, which offered audio narrations of long-form magazine articles. Whelan began to narrate for the company and was later hired as head of production. (The New York Times Company acquired Audm in 2020.) Whelan no longer works for Audm, though she frequently narrates articles as a freelance contributor.

Just before the pandemic, she began “Thank You for Listening,” combining her writing with the experiences she has collected as a narrator.

Writers say that Whelan has helped them understand their own work. “When I listen to Julia read my stories, it sounds like she is calling you over to tell you a great story,” Nuzzi said. “When I write now, I try to think like that, that I am calling a reader over to tell them a great story. It has completely changed my approach.”

When Flynn was preparing to write the screenplay for the film adaptation of “Gone Girl,” she decided against rereading the book, opting instead to listen to the narration. “Julia gave me the benefit of listening to Amy and seeing the world through her eyes,” Flynn said.

Whelan said that she also learns about her writing when she experiences it as a narrator. “There is something about it that changes when you’re performing it,” she said. “I read the book out loud during every stage of its revisions but it’s different when you sit down and have the microphone in front of you, when I finally am inhabiting all the characters and the story comes to life.”