Rhys Bowen lives in a cozy house with her husband of 57 years on a hill in Marin County, north of San Francisco, a place with views of Mt. Tamalpais and a yard that’s a favorite stop for hungry deer and rabbits.

“I don’t have the lovely English garden I always dreamed of, because the animals eat everything,” the 82-year-old British expat author laments over FaceTime on a late spring afternoon from her media room, which is filled with some of the 150 books for kids, teens, and adults—including 56 mysteries and historical novels—that she’s written since moving to the U.S. in 1967. Equipped with professional lighting and a green screen for book club interviews, the room is much more well-appointed than the comparatively small office where Bowen writes, when she and her husband, John, 90, aren’t at their other home, in Arizona. “I like to feel like I’m in a capsule when I’m writing,” Bowen says. “I’m easily distracted and need silence. But I have a husband who tends to come in and say things like, ‘Where did we put those insurance papers?’ There have been times when I’ve wanted to kill him, but we’re still together.”

Revered for her witty prose and irresistible dialogue, Bowen is like the protagonists in her novels: clever, fun, and a pleasure to be around. Her staggering literary output includes the Royal Spyness and the Molly Murphy historical mystery series—the latter of which she cowrites with her daughter Clare—and several standalone historical novels. Her books have sold nearly 10 million copies, in more than 30 languages, according to the Jane Rotrosen Agency, which represents the author, and have been honored with Agatha, Anthony, and Macavity awards.

Bowen’s latest, The Rose Arbor (Lake Union, Aug.), concerns Liz Houghton, an obituary writer in 1960s London whose drab life hits overdrive when she begins investigating the disappearance of a young girl named Lucy. Liz tags along with her roommate, Marisa, a detective with the Metropolitan Police, on a work trip to Dorset, where she learns of the disappearance of three other girls 25 years earlier, during WWII. As Liz digs into the circumstances surrounding the disappearances, her sleuthing takes her to Tydeham, a village that was occupied by the British military during the war and left in ruins. Liz begins to have haunting visions of the girls that make her wonder: is she psychic or just losing it? She isn’t sure, but keeps digging and, as she does, discovers shocking things about Lucy, the other girls, and her own complicated past.

The idea for The Rose Arbor came after Bowen read an article about a WWII-era village that had been commandeered by the British military and used as a practice site for the D-Day invasion. “I saw photos of the creepers growing over the destroyed walls and it struck a chord,” she says. “I started thinking about the girls who had been evacuated during the war. Mothers would take their children with a label around their necks to the train station and hand them over. The train would stop in the countryside and kids would get off and a farmer would say, ‘I’ll take that one.’ Often there was no recordkeeping. How many children disappeared or were abused? That was on my mind, too, and it came together that way.”

For Bowen, building a novel can be scary. She doesn’t outline or plan, preferring instead to be surprised. “This sounds corny, but the characters come to me,” she says. “I say hello and follow what they do. The first 100 pages are intense—I panic—but then I can see the light and rush ahead.” Strong female sleuths are central. “Female empowerment is important. Women against all odds. Women who’ve been underestimated. I like to bring them into the spotlight.”

Danielle Marshall, Bowen’s editor at Amazon Publishing, calls the author the hardest working woman in the business. “She’s delightful, and busy, busy, busy,” Marshall says. “She’s one of the finest authors I’ve ever worked with—and always beautifully dressed.”

Born in 1941 in Bath, England, Janet Quin-Harkin took the pen name Rhys Bowen—her Welsh grandfather’s name—when she began writing mysteries in the 1990s. She never liked the name Janet, even as a kid, and often felt lonely growing up. As a teen she wanted to be a movie star and wrote scripts for herself. “They always ended with everybody sobbing,” she recalls.

After graduating from the University of London in 1963, where she studied modern languages, Bowen worked at the BBC as a studio manager. It was the Swinging ’60s, and Bowen—who loves to sketch, play the harp, and sing—moonlighted as a folk singer at the legendary club Bungie’s and hung out with Simon & Garfunkel. “I had my white vinyl boots and Vidal Sassoon haircut,” she remembers, “and it was great.”

In 1966, tired of dreary London, she moved to Australia to work at the Australian Broadcasting Corporation and met and married her husband—a fellow British expat—whom she followed to San Francisco in 1967. “In Australia, I had visions of dating rugged sheep farmers, and I met this English aristocrat who always wore a tie,” she says. “It was the opposite of anything I intended.” After settling in San Francisco and having four kids, Bowen began writing books for young people—until, she says, “I got burned out on the high school drama”—then turned to mysteries, adding that she always favored cozies over darker noir, which never meshed with her personality. She writes 1,500 words a day, more if it’s going well. “Madness is the word to describe it,” she says of her schedule, “but I like being busy. Even if my husband and I are at a resort, the first day I can sit with a piña colada, but by the second day I’m going to take out a kayak.”

Meg Ruley, Bowen’s agent, says Bowen is a natural storyteller with a special touch. “Whatever book Rhys is writing feels authentic,” Ruley notes. “She has a well of creativity and hasn’t slowed down. In fact, she’s more energized. Send me whatever she’s on.”

For Bowen, the spark never fades—for her writing or her life. “I don’t feel old at all,” she says. “I can be walking down the street and think, ‘Oh, that’s a cute guy,’ and then I suddenly think, ‘Don’t be stupid,’ but it doesn’t change.” A lifelong adventure seeker, she has traveled to India, the Himalayas, and Sri Lanka, and while she’s pretty Americanized these days, she still drinks a cup of English tea at four each afternoon, and can’t resist a bit of Marmite. Her astonishing work ethic has brought her tremendous success, but Bowen is wise enough to realize what truly matters in life. “What’s most important are my friends and family,” she says. “In that way, I’ve been very blessed.”

Elaine Szewczyk’s writing has appeared in McSweeney’s and other publications. She’s the author of the novel I’m with Stupid.