John Green, author of novels The Fault in Our Stars, Looking for Alaska, and Paper Towns, has another film adaptation on his hands. The Fault in Our Stars and Paper Towns previously received film adaptations, while Looking for Alaska received a television adaptation from Hulu. His collection of holiday stories, in conjunction with two other authors, Let It Snow, also received the film treatment from Netflix. The next book to receive the adaptation treatment is Turtles All the Way Down.

The film is currently filming in Ohio, which means it will be a bit before it hits screens, but at least we have the cast announcements to tide us over. The Hollywood Reporter reported in March that Isabela Merced is starring as the main character Aza Holmes, a girl struggling with anxiety and intrusive thoughts. This isn't Merced's first Green adaptation. She was Julie in Let It Snow, a girl that meets a celebrity who helps her make an important decision about her future. Audiences may also recognize her from Instant Family or Dora and the Lost City of Gold. Aza's best friend Daisy will be played by Cree Cicchino (Mr. Iglesias), and her love interest and old friend Davis by Felix Mallard (Ginny & Georgia).

With the characters cast and filming underway, it isn't clear what will make it from page to screen. Inevitably some things will be cut, as is common with adaptations, but there are some plot points that should really be kept in to make it the best it can be. Let's explore what we hope to see in Turtles All the Way Down.

The Struggles of Mental Health

isabela merced let it snow
Netflix

Aza struggles with Obsessive-Compulsive Disorder (OCD). Her obsessive thoughts are related to Clostridioides difficile, a bacterial infection, and her body's microbiome as a whole. This results in her continued use of hand sanitizer and wipes, reopening a wound on her finger to drain it because she feels it's how the bacteria could enter her body, and constantly reading the symptoms of infection to reassure herself she isn't infected.

Related: Turtles All The Way Down: Plot, Cast, and Everything Else We Know

Much of Aza's journey in the book is her coming to terms with the idea of needing a new coping mechanism, though it takes her almost poisoning herself for the realization to hit. Though it seems like the main story is the mystery she and Daisy are trying to solve, it's actually Aza trying to understand and cope with her symptoms as she begins to consider the next chapter of her life.

If any of this were minimized in the film, the main character would become a hollow shell of their book counterpart. It's one of the book's key themes, and it wouldn't make sense to remove or minimize it because of its role in the story.

The Star Wars Fan Fiction

star-wars-chewbacca-lucasfilm
Lucasfilm

Daisy has a unique interest: writing Star Wars fan fiction. It's a big part of her life, and she has some recognition in the community with a supportive fan base and some haters. The ship her writing features around may be controversial (it involves Chewbacca and a human character), but it seems to have given Daisy an important outlet.

Aza doesn't read her best friend's writing, despite the constant begging and pleading. When she finally decides to read some, she realizes one of the characters is based around her, or at least it feels that way.

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The understanding that Daisy needs a way to vent about her best friend, because she can't vent to Aza about Aza's behavior and quirks, creates a divide between them. Aza sees it as a negative thing that maybe her best friend isn't really who she thought she was. This thought increases when she sees the readers' comments about the character, mostly blaming the character for things that go wrong in the story.

But, it also causes her to realize she hasn't always been the best to Daisy, which results in her friend needing an outlet. The whole situation is a significant part of Aza's journey, almost acting like a catalyst, and it would be odd to remove that.

The Tuatara

tuatara turtles all the way down
San Diego Zoo

One of the book's subplots is about the tuatara, a rare not-lizard reptile that Davis' father has left his entire fortune to. If something were to happen to him, his two children would get nothing and be left on their own. According to the San Diego Zoo, they are only native to New Zealand, which means at some point, Davis' father had one brought to the United States. He cares so much about the reptile that he has a keeper on staff to take care of it.

The tuatara as heir to an estate does have an impact on the plot, so without it, it's not clear how the film could get to that same point.

You have plenty of time to read the book and catch up on Green's other adaptations (one of which includes model Cara Delevingne in a career-best performance) before Turtles All the Way Down comes out.