Seth Fishman gave up on his third novel in 2010.
A literary agent who studied with Chang-Rae Lee at Princeton University and represents acclaimed author Téa Obreht, Fishman had written two unpublished books before finishing a thriller about a poison taster. The novel drew interest from publishing houses but his only offer was from a small book packager, which he turned down.
He then took all the drafts of his book and threw them in the trash. "I just didn't want to write anymore," Fishman said. "I found myself at a real dead end."
At the time, authors such as John Green ("Paper Towns" and later "The Fault in Our Stars") and Suzanne Collins ("The Hunger Games") were garnering strong sales and reviews, not to mention pop cultural buzz, with young adult novels. Fishman's agent, Kirby Kim, then with William Morris Endeavor, suggested he try a book aimed at teens. Fishman's voice was suited to the genre, said Kim, who also thought that young adult editors were eager for new material and might buy an unfinished manuscript, something unlikely in the adult market.
"I wouldn't have done it just to be published, but I thought it was a good way to keep writing," Fishman said. So he wrote an outline and 70 pages, which his agent used to sell his novel, "The Well's End." Putnam published it this year.
Fishman has already handed in the sequel. "I don't think that would've happened that way if I wrote another adult book," he said.
Many established authors, including Michael Chabon and Joyce Carol Oates, have dabbled in writing books aimed at teens. And some well-known children's authors, such as Daniel Handler, who writes the "Lemony Snicket" series, started with books for adults.
But as the YA genre has become more popular with both teens and grown-ups, some authors say the line between adult and children's writing seems more fluid than ever.
Rainbow Rowell published "Attachments," a novel about a man who falls in love with a woman after secretly reading her emails, in 2011. Her next book, "Eleanor & Park," was about two high schoolers; when it launched in Britain, it was marketed toward adults. But Sara Goodman, her U.S. editor at St. Martin's Press, bought Rowell's book as a young adult book, knowing it could be cross-marketed.
"It was really just a gut feeling," said Goodman, who mainly works with young adult writers but also has edited commercial women's fiction.
"Eleanor & Park" became a bestseller, as did Rowell's next book, "Fangirl," also categorized as YA. Yet her latest, "Landline," out next month, will be marketed toward adults.
"To me, they're just stories I want to write," Rowell said. "I didn't do anything differently."
The transition has been harder for other authors. Sophie Littlefield had written comedic crime novels about a middle-aged female vigilante in Missouri that also featured a funny, foul-mouthed kid named Todd. When she handed in her second book, her agent, Barbara Poelle of the Irene Goodman Literary Agency, suggested she take a shot at something younger.
"There was a tone and quality to how Sophie wrote the teen character," Poelle said, that made her think Littlefield could write young adult.
But Littlefield said it took some time to understand the category. The 50-year-old author had loved "The Chronicles of Narnia" as a child, but said her daughter "wanted a faster plot."
Still, Littlefield said she found some similarities between contemporary young adult books and works from her childhood. Young adult "protagonists are, at their heart, asking, 'Is there a place for me in this world?'" she said. "And who can't identify with that?"
Littlefield's first young adult book was published in 2010, and she has finished three more while also continuing to write in other genres.
Philadelphia-based novelist Elisa Ludwig began writing young adult books after a mentor read one of her short stories about a 15-year-old girl. "This is a market where publishers are buying more books, it's an enthusiastic readership," Ludwig recalled her mentor saying. "If you enjoy writing about teens, this might be a good fit."
Ludwig, who got an MFA from Temple University and is an Alice Munro devotee, was unsure if she could make the switch. But, she said, "I quickly realized, that, to me, it was more meaningful if I could do work that would entertain and enlighten a kid rather than just writing clever things for myself."
The community of young adult readers and writers was surprisingly welcoming, said Ludwig, whose latest book, "Coin Heist," came out last week. "It feels like I've found my tribe."
Rowell also has noticed a difference in how her books are received. She interacts with fans of her young adult books on social media and at readings. "I get Twitter messages from 'Eleanor & Park' fans all the time. It has been so delightful for me," she said. "There was really none of that for the adult book."
Now that the cineplex is teeming with YA adaptations ("Divergent," "The Fault in Our Stars," "The Book Thief"), Goodman said she regularly sees proposals from adult authors who are trying to break into the children's market. But not all of them are successful.
"It's all about voice," she said. "It's extremely hard to understand the teenage mind and get the dialogue right."
As for Fishman, he was used to writing in different genres and didn't feel the transition to young adult writing difficult once he found the voice of his protagonist, a 16-year-old girl named Mia who attends a prestigious boarding school that becomes the site of a virus outbreak. His book has an ambiguous ending that would fit in an adult thriller.
"I had an audience intelligent enough to read anything, so I definitely didn't want to write down to them," Fishman said. "It was tremendous fun to set up a story where the reader would start somewhere familiar and end up somewhere completely different."