In 1982, Hope Dellon, who had been an editor at St. Martin’s since 1975, was approached by agent Barbara Lowenstein about a series of Regency romances, the Six Sisters. As Dellon recalls, the proposal “was so smart and charming I had to buy it.” Dellon felt as strongly about the author, Marion Chesney, now better known by her pseudonym M.C. Beaton. “Marion lived in Brooklyn then, and I had lunch with her every chance I got because I liked her so much; she was witty and kind, and she told great stories about her early adventures as a bookseller turned newspaperwoman in Glasgow and London.”

The rest, as they say, is publishing history: more than three decades after Lowenstein’s successful pitch, the author-agent-editor triumvirate is still going strong. In September, Minotaur released The Blood of an Englishman, the 25th cosy whodunit featuring Agatha Raisin, described by PW as a “Miss Marple who enjoys drinks, cigarettes, and men.” Together, books in the series have sold more than two million copies in North America alone; the December release of an Agatha Raisin TV pilot on the U.K.’s Skye 1 channel is sure to add to her legions of fans.

For Beaton, who was born in Scotland in 1936, the biggest influence on her novels was her “early days as a bookseller” in charge of the fiction department at John Smith & Sons Ltd. “You need to love books to write them, and how I loved all the storytellers from Muriel Spark to J.R.R. Tolkien,” Beaton recalls. Her stint as a crime reporter for the Scottish Daily Express had less of an impact, “because any villains I knew were pretty subnormal,” and nothing about them stuck with her.

Beaton’s transition to writing novels was a gradual one. She moved to the U.S. in 1971 and waited tables, after her husband, Harry Scott Gibbons, got a job here. Looking to be more present for her son, Charles, Beaton began writing the romances that caught Lowenstein’s attention, and then Dellon’s.

In 1985, Beaton created her first series sleuth, Hamish Macbeth, whom she describes as a “laconic, unambitious Highland-village policeman” with a quick wit. The first Hamish novel, Death of a Gossip, was inspired by a fishing holiday marked by tensions in the small group Beaton was part of. She used that experience as the starting point for her plot—a guest at a fly-fishing school is murdered, and Hamish has his first real crack at a homicide investigation.

By the time the series reached its seventh book, Beaton had relocated to the Cotswolds, in rural southern England. A meal with Dellon, while the editor was visiting on a business trip, led to a new direction: Dellon found that Beaton “told me such terrific stories about her village, and the people who lived there, that we somehow started talking about the Cotswolds as a possible setting for a series about an amateur sleuth. I think she came up with the name Agatha Raisin on the spot.”

Agatha debuted in 1992 in Agatha Raisin and the Quiche of Death. Both she and Hamish remain close to their creator’s heart. “Because of the recent Scottish referendum and all that, someone of my age, brought up during World War II, thinks of herself as British. So part of me is as Scottish as Hamish and the other part as English as Agatha.”

For Dellon, there’s no mystery about Beaton’s appeal: she is, the editor says, “sharply observant and plain-spoken, with no time for arrogance or pretension, but with insight and sympathy for the underdog. She is also very funny. I believe that her books are a pleasure because they’re exactly the same. I’ve known so many people over the years who say something like, ‘I never read detective stories, but I came across one of hers and loved it.’ ” Three decades on, Beaton, whose fans include the former Archbishop of Canterbury and actor Elizabeth Hurley, is surprised by how much she’s produced. “I don’t know how I have managed to write 160 novels. I didn’t get that much money for a long time, so I just accepted any contract that came along.” But she would be the first to admit that credit for her success must be shared with her longtime collaborators, Dellon and Lowenstein. Lowenstein sees Beaton’s success as a major highlight of her own 40-year career as an agent: “I think we can honestly say that the three of us respect and admire each other and all want the same thing. We work together beautifully to make it happen.”

Click here to return to the main feature.