The unnamed narrator recounts his childhood from the perspective of an adult trying to piece together his past. As a young boy with curly brown hair, he lives with his single mother and spends his free time mapping and exploring the vast woods behind his house. He naturally gravitates toward warm connections, seeking safety and comfort in his friendships despite the strange occurrences happening around his neighborhood.

A hardworking single mother raising her son in a growing suburban community. She is fiercely protective, instituting rigid boundaries and rules to keep him safe from the surrounding woods. When strange incidents begin to occur, she takes immediate action to secure their living situation, prioritizing her son's physical safety and sense of normalcy over absolute transparency.

An enigmatic, anonymous adult man who becomes fixated on the young narrator. He begins his correspondence by sending poorly composed photographs through the mail without a letter or return address. Over time, his presence manifests as a looming, invisible threat that steadily infringes upon the narrator's daily life and personal spaces.

The narrator's childhood best friend, recognizable by his straight blonde hair. Josh comes from a slightly more affluent neighborhood but happily joins the narrator in ventures like selling snow cones and drawing detailed maps of the local creeks. The two boys are virtually inseparable during their early years, often mimicking each other's habits and communicating via walkie-talkies when apart.

Josh's older sister. The narrator develops a quiet crush on her during their childhood, which later blossoms when they bump into each other at a local movie theater known as The Dirt Theatre. She is initially hesitant to discuss her family's past but eventually forms a close, text-based connection with the narrator during their high school years.

An elderly woman living in a colonial-style house by the lake in the narrator's first neighborhood. She suffers from Alzheimer's disease and frequently confuses the narrator and Josh for her estranged adult sons, Chris and John. She often offers the boys snacks and tosses them pool toys when they swim near her property.

Josh and Veronica's father. He lives in a nicer part of town and takes an active role in parenting, ensuring the boys are held accountable for their actions. He strongly believes in the importance of honesty and occasionally takes on extra odd jobs around town, such as leveling lots and filling holes for local property owners.

Josh and Veronica's mother. She raises her children in a comfortable suburban neighborhood, pooling resources with the narrator's mother to buy the boys walkie-talkies so they can easily stay connected across town.

The narrator's pet cat, brought into the home to cheer him up after he breaks his arm falling from a tree. Boxes is highly adventurous, frequently escaping the house to hunt bugs and explore the dark crawlspace beneath the floorboards.

A large classmate of the narrator. He begins sitting with the narrator simply because he is too shy to speak to him directly. His primary motivation for the proximity is his massive crush on Veronica, hoping the narrator can eventually put in a good word for him.

A childhood classmate who eventually reenters the narrator's life during their freshman year of high school. He introduces the narrator to a new circle of friends that frequently attends movie screenings at a local, run-down venue called The Dirt Theatre.

A coworker of the narrator's mother. She drives a car without a back seat, which inadvertently forces the mother to leave the boys home alone when an emergency shift suddenly arises at their workplace.

Mrs. Maggie's deceased husband. He was a commercial jetliner pilot who died of a heart attack while jogging near the narrator's house shortly before a planned retirement trip. Mrs. Maggie's deteriorating condition leaves her constantly waiting for his return.