In August 2018, Kate DiCamillo was in the office of her Minneapolis home, sorting through a decade's worth of old papers and manuscripts, when she happened upon a stunning discovery — the first 40 pages of a long-abandoned, long-forgotten novel.

She sat on the floor and read with growing excitement, while outside her windows the cicadas sang.

"I was like, what's this? And because I had been so long away from it, I was able to read it like it wasn't something I had done, and I could tell that it had legs," she said. "It was like, oooh, boy! This is something!"

Those 40 pages — begun in 2009, six months after the death of her mother, Betty — have grown into a full book of 256 pages, to be published Sept. 28. "The Beatryce Prophecy," DiCamillo's 10th novel for middle-grade readers, has earned starred reviews from trade journals Publishers Weekly and Kirkus, which called it a book with "an angelic soul."

The story of young Beatryce, a lost and terrified child who is found hiding in a haystack, guarded by a fierce goat named Answelica, is set in some other time, some other place.

War rages. Girls are not allowed to learn to read, but somehow Beatryce can both read and write. Monks keep a book of prophecies. One prophecy states that a girl will unseat the king, and when the book opens, the king and his henchmen are on a mission to find and capture Beatryce.

As with many of DiCamillo's books, the novel is about a parentless child, benevolent adults, a difficult world, a beloved animal. It's about the power of friendship, love and story, and though it is dark at times, it glows with hope.

Dedicated to her own strong mother, it is also the most feminist story DiCamillo has told.

"That went whizzing right past me until I turned it in," she said. "It wasn't a conscious thing at all. But I can see it and I get behind it 100 percent."

With its resourceful protagonist — not to mention the fearless Answelica — the book carries the message that girls can be their own saviors.

DiCamillo will launch it Sept. 30 at Talking Volumes, her first in-person appearance in nearly two years.

The author is sitting on a bench overlooking Lake Nokomis as she talks. On this August afternoon she is dressed in a long-sleeved blouse and jeans and she is drinking hot coffee. She has kicked her leather sandals off her tanned, bare feet.

The walking path is behind her, but somehow she is aware of every person who passes. She notices a couple she'd seen at the coffee shop — or their small dog, anyway. "Oh, there goes that dog, go grab him," she whispers.

Two people jog past. "They're running along and they don't know that someday they won't be able to run along," she says. "They're like, yeah, we'll be able to do this forever."

One wonderful parent

DiCamillo, who is 57, grew up with her mother and brother in Clermont, Fla., where they settled when she was 5, moving from Philadelphia for the warmer weather. Her father was supposed to join them, but he never did.

It is her mother, Betty Gouff DiCamillo, whom Kate credits with keeping the household rock-solid, filling her head with stories, teaching her to believe in herself, teaching her to read.

"I was always desperate to read," she said. "And I went off to first grade thinking, finally, it's going to happen the first day. And, of course, it didn't."

It didn't happen the second day, either, or the third. The teacher taught phonics, which made things worse; DiCamillo couldn't understand them.

"I came home and collapsed in front of my mother, hysterical, like, I can't do it! I want to read! And I don't understand any of this! And my mother was like, 'For the love of Pete, calm down. We'll just work around it.' " She made flashcards, and every day after school they went through the pile until Kate had memorized them all.

"So that's why the book is for her," she said. "Because she said there are lots of different ways to do it — we'll find a different way."

Yes, DiCamillo grew up with just one parent. "That's all you need, is one wonderful one," she said.

Writing through the pandemic

The year 2020 was supposed to be a big one for DiCamillo. The Minnesota Opera was to stage "Edward Tulane," based on her novel "The Miraculous Journey of Edward Tulane" and the Royal Shakespeare Company in London was to stage a musical version of "The Magician's Elephant."

COVID-19 put a stop to both, but the lockdown had an unexpected upside: It gave her time.

For the first 100 days, "I wrote every morning." She wrote fairy tales. She wrote stories. "It's been a productive time for me." She has "stuff lined up into, I don't know, 2025."

This year is proving to be a slow, cautious reopening. The London musical is set to open Oct. 14 in front of a live audience, but the Minnesota Opera has not rescheduled "Edward Tulane." In the meantime, it will offer a preview, a virtual concert with choral highlights beginning Dec. 13.

"The Beatryce Prophecy" was illustrated by Australian artist Sophie Blackall, a two-time winner of the Caldecott Medal who joined forces with DiCamillo, herself a two-time Newbery medalist. The book has the feel of a medieval illuminated manuscript, with full-page illustrations, elaborate borders and decorative dropped initials.

But that medieval feeling might be misleading. The last page gives a clue: "All of this happened long ago," it says. "Or perhaps it has yet to happen. ... Who's to say?"

On the park bench at Nokomis, DiCamillo repeats the question: "Who's to say? Perhaps things have ended and started over."

A few years ago, she was in England. As she stood in the peace of the ancient Roman pools at Bath, "somebody flew a drone through," she said. That combination of ancient and modern "was the most disconcerting and also most oddly moving thing."

That feeling is echoed in "Beatryce" — the medieval with a whiff of the modern. Stories, DiCamillo notes, "are smarter than I am." Even her own.

"I really feel like it's the future. But I don't know," she said, staring out at the lake. "I wonder along with the reader."

Laurie Hertzel is the Star Tribune senior editor for books. @StribBooks