John Green, author of the beloved novel “The Fault in Our Stars,” is one of the top writers in today’s YA market. His new novel, “Turtles All the Way Down,” has been eagerly awaited by fans, and shot to the top of the bestseller lists upon release. It focuses on Aza Holmes, a 16-year-old girl who’s struggling to live a normal life despite crippling anxiety and OCD. She compares her mental processes to a spiral that “just keeps tightening, indefinitely.”

There are people in Aza’s life who do their best to help her function. There’s her loving if not always fully attentive mother (Aza’s father died years ago), her psychiatrist, and her best friend, Daisy. And there’s an intriguing distraction available in the form of a local mystery: the disappearance of a billionaire CEO that Daisy wants to investigate. Because Aza used to know the man’s son, Davis Pickett, Daisy nags her to use that connection to help get them into the Pickett estate and help them earn the reward for information on the disappearance.

When Aza and Davis start to develop feelings for each other, it may throw a wrench into Daisy’s plans to get the reward money. But because of Aza’s condition, the romance is destined to be a complicated one. In fact, Aza’s condition is starting to threaten everything in her life, including her relationships and her goals for the future.

Green has OCD himself, and his description of Aza’s mental battles rings true. She’s terrified of bacteria, to the point that she keeps reopening, cleaning, and re-bandaging a wound on her finger. And though her medication can’t make everything completely better, her decision not to take it makes things much worse. Before the story is done, she’s resorted to drinking hand sanitizer in a desperate attempt to cleanse herself.

Although Aza, like most of Green’s teenage characters, is hyper-articulate and bright, she has trouble trying to explain to those around her the terrible fear that drives her to do these things. But she has to learn to keep trying, to keep reaching out and sharing her pain and fear, in order to have any hope at all. And she has to learn to care more about her family and friends, and not think only about herself, for her relationships with them to truly work.

Green has a knack for creating appealing characters, but he doesn’t always give them a lot of depth. Aza and Daisy are interesting and often likable characters whose friendship deepens over the course of the novel, but several of the other characters come across as one-dimensional. Davis in particular, though admirable in many ways, doesn’t have much of a character arc. Aza’s mother warns her that he might be trouble because rich people tend to use others, but we never see this in Davis. That trait is reserved for the callous father who abandoned him and his troubled younger brother, forcing Davis to act the role of father himself.

As for content issues, the worldview is basically nonreligious (despite the occasional Bible quote), the profanity is pretty frequent, and there are several sexual references. The teenagers generally have an anything-goes view of sexuality, although Aza’s fear of bacteria and germs prevent her from going very far with Davis. Daisy gets caught in bed making out with her boyfriend, but doesn’t actually lose her virginity to him — though not for lack of trying. It’s disturbing to see her make fun of his desire to wait for sex until he’s in love. However, on the plus side, Green does recognize some of the distinctions between friendship and romantic feelings, rather than blurring the line between them as many YA authors tend to do. Though the girls occasionally joke about the idea of sexual attraction to each other, they make it clear that there actually isn’t any.

Green always strives for realism in his books — one reason they’re so popular — and a lot of young readers will relate to these characters and be drawn to their good qualities, such as their efforts to be more caring and less selfish. But parents should be aware of the more troubling aspects of that realism.

Note: This will be the last Youth Reads review at BreakPoint, as my last day here is November 10. Thanks to our readers for all your support and appreciation over the years!

Image copyright Dutton Books for Young Readers. Review copy obtained from Amazon.

Gina Dalfonzo is editor of BreakPoint.org and Dickensblog, and the author of “One by One: Welcoming the Singles in Your Church” (Baker, June 2017).