On what passes for a cold day in the San Francisco Bay Area, Jacqueline Winspear arrives at a coffee shop clutching a black bag with a bright peacock design. The bag, she explains, is called Yali’s Carry On, and it was made by a college student who learned about art as a child during years undergoing cancer treatment at Chicago’s Children’s Hospital.

“It’s called Carry On,” says Winspear, “because we all have to carry on.”

The bright bag with its “get on with it” spirit not only appeals to Winspear, but also epitomizes the spunk and tenacity of Maisie Dobbs, the former nurse–sleuth Winspear created more than a decade ago. Since then, Maisie has been solving mysteries in London during the interwar period. Born and raised in Kent, England, Winspear immigrated to the United States in 1990, but her fiction celebrates the spirit of the first women in modern times in Britain to work in a war effort. In March, HarperCollins will publish the tenth book in the series, Leaving Everything Most Loved.

Before Lady Edith begged her “papa” on Downton Abbey not to chase away an older suitor because the war left so few marriageable men, Maisie Dobbs represented a generation of women who had to just “get on with it” after the war left them facing very different, often unchartered, lives. According to the 1921 British Census, Winspear quotes, there were two million “surplus women” of marriageable age; more than 750,000 men died in the World War I.

Since Maisie Dobbs debuted in 2003, Winspear’s character has been called “beguiling” (PW), “a heroine worth cherishing” (New York Times) and was even named by first lady Laura Bush as a favorite. From the start, Winspear’s mysteries have won awards (including two Agathas and an Edgar nomination) with An Incomplete Revenge (Holt, 2008) and Among the Mad (Holt, 2009) hitting the New York Times bestseller list immediately after their release.

The character came to Winspear’s mind fully formed, she says, and wearing her signature cloche hat, ascending out of a London tube station. And while Winspear had done some freelance writing, she had never written a novel before, and held a day job at a telecommunications company (a job she told a friend she’d give her right arm not to have to do). Two days later, Winspaer broke her right arm in a horse-riding accident. Her friend, memoirist Adair Lara, said, “You’ve got a left arm haven’t you?” With that push, Winspear wrote her novel and agent Amy Rennert sold the book to Soho within a month.

Over the course of the series, Winspear has filled out the story of Maisie and those around her in a way that shows “ordinary people doing extraordinary things,” as the author likes to describe the spirit of Maisie’s times. Following her mother’s death, Maisie’s horse groom father helped his teenage daughter secure a position as a kitchen maid in a grand house, where, after being caught by the lady of the house sneaking into the library to read, she was given the opportunity to study with a renowned investigator/psychologist and friend of the family. She later lied about her age to serve as a nurse during WWI and was wounded in a raid on the field hospital where she worked alongside her boyfriend Simon, a doctor whose injuries caused him to lose his mind. . Maisie perseveres and hangs out a shingle as an investigator, though she’s often pushed into having fun by her gin-and-tonic-drinking, wealthy, best friend Priscilla. She delights in being “Tante Maisie” to Pris’s houseful of boys.

“The seedlings of every book [in the series] have been there for years,” says Winspear, who adds that she still feels like a rookie writer. Her plot lines are usually rooted in her own memories or family stories. Her father’s recollection of a young mentally challenged horse whisperer he knew in his childhood found its way into Elegy for Eddie. In Leaving Everything Most Loved, a murdered woman who had left her native India is central to the plot, and Winspear’s face lights up when she remembers an Indian teacher who surprised a class of 10-year-old girls with saris from her closet for them to don for the day.

“Picture it—a cold dreary British school, and there’s this teacher in a different, bright sari every day,” Winspear says.

In Leaving Everything, Maisie’s latest case—which begins with the murdered Indian woman’s brother coming to Maisie with concerns about Scotland Yard’s less-than-thorough investigation—gives her the itch to travel. But what of James Compton, the son of our heroine’s one-time benefactor/employer, who keeps asking Maisie to marry him? Will Maisie get on with it? Winspear says she will, but adds that book 10 does not exactly make clear what the “it” is. She can only confirm that Maisie will keep going. We’re picturing a steamer trunk... with a peacock design.