A Hugo and Nebula Award nominee, Yoon Ha Lee writes sophisticated science fiction for adults. So when his agent wondered whether he had any interest in creating a middle-grade adventure story based on the folklore of his native Korea for a new imprint, he hesitated — but only for a moment.

“Honestly, the deciding factor was working with Rick Riordan, someone my daughter really looked up to,” said Lee, who lives in Baton Rouge with a voracious seventh-grade reader. “She has read every single one of his books.”

Lee and two other authors will be the first to publish novels with Rick Riordan Presents, Disney-Hyperion’s newest imprint. The publisher has also signed Jennifer Cervantes’s Storm Runner, a standalone middle grade novel about a 13-year-old boy who must save the world by unraveling an ancient Mayan prophecy, and a middle-grade quartet from YA fantasy author Roshani Chokshi, the first book of which is titled Aru Shah and the End of Time. Chokshi’s book will publish in April 2018. Lee and Cervantes will both debut in September 2018. Audio rights to all of the titles have been sold to Listening Library.

The idea for the new imprint stemmed from the repeated requests Riordan gets from fans who can’t get enough of his mythology-based thrillers. Together, Riordan’s novels about Percy Jackson and the Olympians, the Kane kids, Magnus Chase, and the rest have more than 86 million copies in print. Riordan currently has his hands full finishing the third installment in his series based on Norse mythology, The Ship of the Dead (Oct.), the cover of which is revealed here exclusively for the first time.

Riordan paused from his own writing to work with editorial director Stephanie Lurie in selecting manuscripts for the imprint, which has a goal of publishing stories from underrepresented cultures and viewpoints. Cervantes’s main character, Zane, must not only grapple with a family history that connects him to the Mayan gods, but with newly acquired knowledge that his ancestry may have something to do with a leg deformity that requires he use a cane — not the greatest reality for a middle schooler.

Chokshi’s heroine is a 12-year-old Indian-American girl who unwittingly frees a demon intent on awakening the God of Destruction. (As Percy Jackson might say: “Oops.”) Her agent, Thao Le of Sandra Dijkstra & Associates, calls it “Percy Jackson meets Sailor Moon with a great wealth of wonderful Indian mythology that is inspired by Roshani’s heritage.”

“The spunky heroine and the myth-conscious storyline made pitching to the new Rick Riordan imprint an incredibly fitting choice,” Le said. “While we had keen bids from a couple of other houses, ultimately, the draw of Rick Riordan, who has been incredibly hands-on with this new imprint, was a deal maker.”

Lee’s book, Dragon Pearl, a standalone middle grade novel, stars Min, a teenage fox spirit whose brother is missing and thought to have deserted the Thousand Worlds Space Forces in order to find the pearl of the title, an artifact that may have the power to save their struggling space colony. Lee says the toughest part of writing for a new audience was working with shorter chapters and a different vocabulary; the idea for the story itself came to him quickly. “I was pretty sure nobody else would come up with a space opera based on Korean mythology,” he said.

Like Lee, Cervantes’ decision to go with Riordan’s new imprint also had a lot to do with her own children’s reading habits. The mother of three daughters, she says all that her youngest child, now 18, read during middle school were Riordan’s books. When she told her she was publishing her second novel (following Tortilla Sun, 2010) with a new imprint founded by Riordan, Cervantes says her daughter turned fangirl in a flash. “She almost forgot to say, ‘Congratulations,’ ” Cervantes said. “The next thing out of her mouth was, ‘Do I get to meet him?’ ”