NEW YORK (AP) — Author Shannon Messenger can now see the end for her telepathic heroine Sophie and the million-selling middle-grade series “Keeper of the Lost Cities.”

Aladdin Books, an imprint of Simon & Schuster Children’s Publishing, announced Wednesday that a tenth and final volume is scheduled for 2023. The book is currently untitled.

“I knew from the very beginning that Sophie’s story was huge. But it was hard to tell at that point how many books it would take to do the Keeper series justice. I’m incredibly grateful that my publisher and fans gave me the freedom, support, and enthusiasm to let the story unfold at its own pace,” Messenger said in a statement.

“Now I have the space to reveal all of the secrets that readers have been dying to know since book one, and I can’t wait for everyone to read the final conclusion. I promise it will be epic!”

Messenger’s series began in 2012 and became a hit worldwide, with Ben Affleck planning to produce and direct a film adaptation. The ninth “Lost Cities” book, also untitled for now, comes out in 2022.

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