How John Green’s Own OCD Inspired ‘Turtles All the Way Down’: Mental Illness ‘Shouldn’t Define You’

John Green is opening up about how his own lifelong battle with OCD inspired his 2017 novel, Turtles All the Way Down — and how he hopes Max’s new book-to-screen adaptation will help others in their own mental health journeys.

“When I wrote the book, I was recovering from a really bad period of mental health and conscious of the fact that I was recovering thanks to friendships and relationships in my life that made recovery possible,” Green, 46, exclusively told Us Weekly while discussing the upcoming film. “I was also recovering because I had switched up medications and I was using new therapy techniques and all that worked together to help me get to a place where I could live a full life again. But I also knew, and still know, that stuff is fragile and when you live with chronic mental illness; Sometimes you have periods of wellness, and sometimes you have periods of not-so-wellness.”

Green said that while crafting the YA book, he wanted to write about the extreme ups and downs that come with battling mental illness while simultaneously depicting it as “honestly” as he possibly could.

“I wanted to write about it in a way that I hadn't seen it written about that much,” he explained. “Not as something to stigmatize or romanticize, not as an illness that is accompanied by certain superpowers, but instead as a really difficult form of psychic pain that nonetheless shouldn't define you.”

John Green’s Novel ‘Turtles All the Way Down’ Is Getting the Movie Treatment: Everything to Know

For Green, it was important to tell a “true” yet “hopeful” story about mental illness because “hope” remains the “correct response” to struggle.

“Hope is the thing with feathers that perches in the soul and sings the tune without the words and never stops at all,” he said, reciting Emily Dickinson’s poem “Hope Is the Thing With Feathers," before adding, “And I do think that that's true. It's just that sometimes you can't hear it, but it's still singing that bird and you just have to fight and work to get back to being able to hear it.”

Seven years after Turtles All the Way Down hit shelves in 2017, a film adaption of the New York Times bestseller starring Isabela Merced, Felix Mallard and Cree Cicchino is set to hit Max on Thursday, May 2. The movie will mimic the original story, which follows 16-year-old Aza (Merced), a high school student with OCD and anxiety. After reconnecting with her childhood crush Davis (Mallard), she finds herself facing the potential of finding love and happiness despite her mental condition.

Elizabeth Berger and Isaac Aptaker (This Is Us) penned the script, and Hannah Marks (Don’t Make Me Go) serves as director of the film. Green has an executive producer credit on the project, as he did on the adaptations of his Paper Towns and Looking for Alaska novels. With a decade of movie adaptations under his belt — The Fault In Our Stars was his first book to hit the silver screen in 2014 — Green knows he has to give the reins over to his collaborators for much of the creative process. However, how Aza’s mental illness is portrayed in the Turtles All the Way Down movie was something the author insisted he have a say in visually crafting.

“So that was one of the only things I had any contractual say in,” he told Us. “That's what I was most nervous about. And so I wanted to reserve some ability to at least have veto power over that stuff.”

At the end of the day, Green didn’t have anything to worry about. Crediting Marks for her ability to properly capture OCD in a “powerful” and thought-provoking way, he told Us she “really understood from the beginning how to have this visual set of expressions and audio sensations that could really mimic the experience of being in an intrusive thoughts spiral.”

Although the film will inevitably feature multiple changes going from page to screen, there is one aspect of the story Green hopes will still clearly resonate with new and old fans alike: the friendship between Aza and her best friend, Daisy (Cincchino).

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“Hannah really brought to life an observation that Daisy makes at the end of the book, which is that she thought she was in a romance novel, but it turned out she was in a goddamn buddy comedy all along,” Green quipped. “There are two love stories in this, and one is the love story between Aza and Davis, and one is the love story between Aza and Daisy, and you kind of expect the love story between Aza and Davis, but the love story between Aza and Daisy hopefully is a little bit of a surprise.”

He continued. “You don't necessarily see that one coming, and I really wanted that to be the relationship that carries AzA through. And that carries Daisy through, too.”

Turtles All the Way Down premieres on Max Thursday, May 2.