Cricket is a resourceful twelve-year-old girl living in Deerfield, Mississippi. Following the sudden death of her father and the disappearance of her mother, she faces the prospect of being sent away to another state by her aunt. Armed with her father's outdoor survival notebook and a strong desire to reunite her family, she runs away to live in a treehouse near a local ghost town. She hopes to solve a decades-old puzzle her mother left behind, believing the solution will bring her mother home.

Mama is Cricket's mother, a creative woman who recently left her family to search for mysterious birds. She struggles with an unspecified mental illness that causes volatile moods, obsessive fixations, and periods of absence from her home. When she was seven years old, she saw a magical "Bird Room" and received a painted puzzle clue from an eccentric artist.

Aunt Belinda is the ex-wife of Cricket's uncle. She takes Cricket in after the death of Cricket's father, though she displays little warmth toward the girl. As a single mother trying to support her own children, she feels overwhelmed and makes secret plans to send Cricket to live with a distant relative in Kentucky.

Miss Vidalia, known as Miss V., is an older woman who lives in an isolated two-story house near the ruins of Electric City. She loves classic American poetry and carefully guards secrets related to the nearby woods. Her home becomes a crucial location in Cricket's search for the mysterious Bird Room.

Cricket's late father grew up in the company town of Electric City before the local mill shut down. Before passing away from a sudden blood clot at age thirty-eight, he taught his daughter essential wilderness skills. His handwritten survival notebook serves as a vital guide for Cricket as she attempts to live alone in the woods.

Cricket's late grandmother was a stern presence in the family. Before her death, she tried to ensure stability for her daughter and granddaughter, prioritizing proper care and asking Mama for a respectful burial headstone.

Charlene is a small insect rescued by Cricket just before Aunt Belinda drives away. Named after Mama's middle name, Charlene becomes a silent but comforting companion for Cricket in the lonely woods. The insect's natural chirps often encourage Cricket to keep searching for clues.

Bob is an eccentric artist who created the legendary Bird Room that Mama saw as a child. He painted highly detailed, lifelike images of the natural world and left behind a series of clues leading to a hidden treasure. He experienced periods of mental illness throughout his life.

Percy is Miss Vidalia's large, friendly dog. He serves as an attentive listener when Miss V. reads Walt Whitman and Emily Dickinson poetry aloud, providing a welcoming presence at her isolated home.

Great-Aunt Genevieve is a distant relative living far away in Kentucky. Aunt Belinda makes arrangements to send Cricket to live with her, a plan that terrifies Cricket into running away to wait for her mother in the woods instead.