On the basis of a three-sentence proposal, HarperCollins has signed Katherine Applegate, who won this year’s Newbery Medal for The One and Only Ivan, for a middle-grade trilogy that will begin with Endling, likely in 2016. Tara Weikum, v-p and editorial director of HarperCollins Children’s Books, acquired North American rights to the three books in a deal brokered by Elena Giovinazzo of Pippin Properties. The agent, who has represented Applegate for a year and a half, was as intrigued as the author was when she read the definition of “endling,” which appears on Wikipedia: “One of the proposed names for an individual animal that is the last of its species or subspecies.”

Intrigued by the word, Applegate dashed off a brief, vague book proposal based on it, and sent it to her agent, who liked the idea. “This is the first time I’ve made a deal based on such a short description,” Giovinazzo said. “We were looking for a new home for Katherine at HarperCollins, since her editor, Anne Hoppe, had left to join Clarion in January, and we decided Tara would be a wonderful match for her. Since we hadn’t yet lined up a project for the two of them, this was a great idea to pitch to Tara. And lo and behold, she liked it.” Though the agent declined to specify the terms of the deal, she noted, “It was a significant deal befitting a Newbery-winning author who also has an incredibly successful commercial track.”

Applegate explained that it was her son Jake who came across “endling” on Wikipedia and shared it with his mother. “It seemed so poignant and inherently dramatic that I couldn’t let it go,” said Applegate. “I went back to the word a few times and felt that it was a book, but not just a single title. It was a trilogy. I knew it would be a quest story, and would take some time to tell.”

Though the author hasn’t yet tackled the actual writing of Endling (“I would call it embryonic, and that might be generous!” she said), she has clearly spent some time formulating its premise. “I knew early on that the endling is an invented, dog-like species with the ability to communicate with humans,” Applegate explained. “The creature travels to the legendary outpost of the last of his kind, and at that point it becomes a quest novel. I have a sort of Seraphina meets Watership Down in my head. I have a file full of notes and bits and pieces. It’s a jigsaw puzzle that I’m slowly putting together.”

Weikum is confident that Applegate will piece Endling together seamlessly. “We all know how talented Katherine is, in so many genres,” she said. “She has written great literary novels as well as books that speak to a large audience. I think Endling will be epic in scope and will have a somewhat classic feel. It’s an animal fantasy, which obviously Katherine can do very well. I am very excited to see what she will do with this trilogy.”

Applegate has several other book projects percolating as well. She is bringing Ivan’s story to a younger audience in a picture book, Ivan: The Remarkable True Story of the Shopping Mall Gorilla, illustrated by G. Brian Karas and edited by Hoppe, due from Clarion in October 2014.

Earlier this year, she signed a deal with Jean Feiwel at Feiwel and Friends for two stand-alone middle-grade novels, likely to be published in 2015. The author and editor have a long shared publishing history. While at Scholastic, Feiwel edited Applegate’s hugely successful Animorphs series, written with her husband Michael Grant, which encompasses 63 books and has sold some 35 million copies since its 1995 debut. And Feiwel encouraged Applegate to write her first stand-alone novel, Home of the Brave, which appeared on the debut Feiwel and Friends list in fall 2007 and went on to win several awards, including a Golden Kite Award and the Josette Frank Award.

And how has Applegate’s writing life changed since The One and Only Ivan – which has sold 500,000 copies and has remained on the New York Times bestseller list for a consecutive 33 weeks – clinched the Newbery? “Even now, I’m not sure that winning the award has entirely sunk in,” she replied. “As a writer, nothing really changes. I’m still the person with a blank page in front of me! On another level, it’s so great to know that Ivan’s story will linger and will stay on the shelf.”