Sarah Prineas has a young reader of the children's magazine Cricket to thank for the impetus that led to her very splashy debut—a three-book contract, two starred reviews for the first volume, and 13 foreign rights sales. Prineas had written only three lines of a story—A thief is a lot like a wizard. I have quick hands. And I can make things disappear—when she came across a letter to the editor in Cricket from a reader who wanted “more stories with wizards and magic.”

“I'll turn that into a story for Cricket,” thought Prineas about her three lines about the thief with fast hands. “So I kept writing.”

The short story became the first chapter of The Magic Thief (HarperCollins), a middle-grade fantasy about the guttersnipe, Conn, whose talents as a pickpocket lead to an apprenticeship with a powerful wizard in a city desperately in need of new magic. Reviewers noted Conn's appealing narration, which speaks conversationally and conspiratorially, to the reader.

“It's the first thing I've written for children, but I feel like I've found my voice, and the thing I want to do,” said Prineas, who heretofore had published only short stories in fantasy journals. She read the first draft of The Magic Thief at Blue Heaven, a writers' retreat in Ohio two years ago. She went back last year with book two, and this month shared the third installment with the group, which had been comprised of writers mostly at work in the adult science fiction and fantasy market.

“That first year I was on the only one writing for children but now there are four and five. It's starting to spread,” she said.

A fellow Blue Heaven writer referred her to his agent, Caitlin Blasdell of Liza Dawson Associates, who sold the trilogy to Melanie Donovan at HarperCollins.

“I had fallen in love with another book Caitlin had but was not quite quick enough in responding and I lost it,” Donovan said. “Caitlin said, 'I feel awful but to make up for it, I have this fabulous story by a first-time author and I'll give you first crack at it.' ” This time, Donovan acted fast. Foreign sales rolled in even faster.

“I thought that it was something special, but you never know how people will respond,” Donovan said. She needn't have worried: the first person she gave it to—one of Harper's British scouts—“in love with it,” said Donovan. The reaction was the same from readers in France, Greece, Romania, Italy, Finland, Spain and six other countries.

“It was like lightning striking,” Prineas recalls, but the foreign excitement also meant they needed a finished manuscript fast. Revisions were completed in two weeks, while Prineas was coping with Lyme disease. “I did the whole thing with a 102-degree temperature. I don't even remember most of it.” Donovan says that was possible because the manuscript had come in clean, already having been vetted by Blasdell, a former fantasy editor at Harper Eos. “By the time it got to me it was in very good shape, especially for a first-time author. Sarah is one of those writers who has really worked to learn her craft.”

That said, novelist was not her first career choice. Prineas studied English literature, first at Minnesota's Carleton College, and then earning a Ph.D. from the University of Arizona. She intended to teach, until she wrote a story for an online workshop while she was supposed to be finishing her dissertation. The story was praised, and the teaching idea shelved, though she has taught at the University of Iowa where she holds a part-time job coordinating scholarships. Her husband, John, a physicist, is also on the faculty, but his research lab is currently under water—a casualty of the “once-in-500-years” flood that has ravaged the area. He is thanked in Prineas's acknowledgments as her “best critiquer,” though she relies on her kids, too—Maud, 12, and Theo, 8.

“When I'm blocked on a plot point, I go for long walks with Maud and talk it through. She always helps me figure out what happens next,” Prineas said. “And Theo gave me a great idea for book two. They're both full participants in this.”

Prineas has felt an itch to write a fourth book about Conn and his master—a quartet, or perhaps more, all sprung from that one short story she initially wrote for Cricket, which, by the way, did not buy it. “They're still considering it,” she said.