Turtles All the Way Down by John Green tells the story of Aza Holmes, a teenager living with OCD and intrusive thoughts.
With her best friend Daisy, she investigates the disappearance of a billionaire, Russell Pickett, and reconnects with his son Davis, with whom she forms a complicated relationship.
While there is a mystery plot, the novel mainly focuses on Aza’s mental health struggles, anxiety, and how her thoughts affect her daily life and relationships.
In the end, the mystery is solved, but the main journey is Aza learning to cope with her condition and keep moving forward despite it.