Reese Witherspoon Talks New Fiction With Harlan Coben (Exclusive)

Reese Witherspoon is heading into uncharted territory.

At Hello Sunshine’s Second Annual Shine Away Conference, the Big Little Lies actress, 48, tells PEOPLE about how her upcoming novel that she’s co-writing with Harlan Coben is different than anything she’s done before.

“It’s scary. Trying new things I’ve never done,” she says. “I’ve written children’s books. I’ve written books about my upbringing in the South, but this is just completely fiction and it’s a thriller, so it’s a genre book as well.”

Witherspoon published Whiskey in a Teacup in 2018 and is also the author of the Busy Betty children’s book series.

Witherspoon also praises her co-author, bestselling thriller author Coben, 62. “That’s why I feel really lucky to have a partner in Harlan Coben, who’s so accomplished and he just helps guide me through that whole process,” she continues. “But it’s really fun digging into the character.”

When asked if her and Coben’s writing process involves late-night emails and phone calls, the Legally Blonde actress adds that it includes “weird sharing of articles that have to do with the topic.”

“So it’s really fun,” she adds.

The upcoming thriller, which is currently untitled, is slated to be published in the fall of 2025 by Grand Central Publishing, an imprint of Hachette Book Group.

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“To say I am a fan of Harlan’s body of work is a massive understatement … the fact that he found my idea for this thriller intriguing enough to want to partner with me on it as co-author is a dream becoming a reality,” Witherspoon said in a statement about the project on Oct. 2.

“Scheming with Harlan on how to thrill audiences with mysterious characters and complex narrative twists and turns has already been more fun than I can describe,” she added. “I can’t wait for everyone to read what we have been imagining.”

Coben, who said he’s been a longtime of Witherspoon and Reese’s Book Club, is also excited to collaborate.

“Once we began discussing her idea, there was no turning back,” he said in a statement. “Collaborating with Reese has been a pure joy and so creatively rewarding. I could not be more excited about putting this novel out into the world.”

The upcoming thriller novel will be published on Oct. 14, 2025. It’s available for preorder, wherever books are sold.