Alice is a nine-year-old girl who grows up by the sea, carefully monitoring her father's volatile moods. She loves reading library books and spending time in the garden, where she learns the secret meanings of native Australian plants from her mother. After a devastating fire leaves her orphaned, she loses her ability to speak and relocates inland to a flower farm with a grandmother she has never met. She relies on the language of flowers to communicate her feelings when words fail her.

June is Alice's paternal grandmother and the owner of Thornfield Farm, a thriving inland flower property that functions as a sanctuary for women. She creates jewelry from pressed flowers and actively practices her family's tradition of floriography. While she offers Alice a physically safe environment, she aggressively controls information and drinks whiskey to cope with the painful history she refuses to discuss.

Agnes is Alice's mother, a woman who finds her only true peace while working in her garden. She lives in a perpetual state of high alert due to her husband's physical abuse, attempting to manage his temper to keep Alice safe. She passes down her extensive knowledge of plant symbolism to her daughter, teaching her that flowers can express emotions when it is too dangerous to speak.

Dylan is a ranger working at Kililpitjara National Park in the Australian desert. He is charming, handsome, and immediately magnetic, quickly drawing Alice into a passionate romance. He insists on spending all his time with Alice, asking her to change her work schedules so they are never apart, and uses the affectionate nickname "Pinta-pinta" (butterfly) for her.

Clem is Alice's father and Agnes's husband. He is a skilled woodworker who keeps his intricate carvings locked in a private shed. He dictates the terms of his family's existence through fear, demonstrating extreme volatility that shifts rapidly between affection and severe physical violence.

Oggi is a young boy from a Bulgarian immigrant family who becomes Alice's neighbor. Because he faces bullying at school over his cultural background, he finds a kindred spirit in Alice. Sweet and highly talkative, he balances Alice's initial muteness and shares her deep love for the nearby river.

Sally is the local librarian in Alice's coastal hometown. She treats the young girl with gentle respect, offering her a safe space among the books before calling for help. Following the tragic fire, Sally stays by Alice's hospital bed to read her stories, carrying immense personal guilt for not intervening earlier in the child's home life.

Candy is the resident chef at Thornfield Farm, known for baking elaborate treats like "Alice blue" cupcakes. Left at the farm as an infant, she was raised by June and Twig and has spent her entire life on the property. She is warm, playful, and loves sharing fairy tales.

Twig is June's right-hand woman and closest friend at Thornfield Farm. She arrived at the property years ago after her own children were taken away by the government, finding a new purpose in helping run the business and raising Candy. She is practical, perceptive, and acts as a grounding force against June's stubbornness.

Lulu is a park ranger working in the desert at Kililpitjara National Park. Also originally from the coast, she bonds quickly with Alice over their shared background. She is highly extroverted, welcoming, and attempts to offer Alice practical advice regarding workplace relationships.

Moss is a veterinarian working in a remote desert town. He is calm, capable, and highly observant, noticing Alice's physical exhaustion and stepping in to help when she collapses from a panic attack. He recognizes that people who come to the desert are often running from something.

Ruby is an Aboriginal woman, artist, and poet working as a ranger at Kililpitjara National Park. She acts as a teacher to Alice, explaining the deep spiritual significance of the desert land and the sacred nature of the local flora. She is fiercely protective of the crater's flowers.

Charlie is Alice's younger brother, who survives the devastating fire that claims their parents' lives. Born prematurely and highly fragile, his existence remains a subject of concern and secrecy for those managing Alice's future.

Brooke is a compassionate hospital nurse who cares for Alice after the fire. She brings the mute child books, including a favorite text about selkies, and provides a gentle, stable presence while Alice processes the initial shock of her parents' deaths.

Toby is a puppy given to Alice by her father as an apology after a violent outburst. The dog becomes Alice's closest companion during her isolated early childhood by the sea, attempting to protect her when Clem becomes violent.

Harry is a massive dog living at Thornfield Farm. June trained him specifically as a therapy dog, and he knows commands to turn on lights and stay close during night terrors, providing constant comfort to Alice.

Pip is a stray puppy Alice rescues upon arriving in the desert. Suffering from mange and malnourishment, she quickly bonds with Alice during her recovery and becomes a constant presence on Alice's daily walks through the national park.

Sarah is a park ranger at Kililpitjara National Park who helps oversee visitor services. She is practical and recognizes that Alice's background on a flower farm makes her an ideal candidate for their open communications position.

Aidan is a ranger working at the national park who lives with Lulu. He acts as the team lead for the park's controlled burns, helping Alice manage her anxiety when dealing with fire in a professional capacity.

John is Sally's husband and a local police officer. He represents stability and kindness in his coastal town, assisting his wife when she finds Alice sneaking into the library and later responding to the fatal fire at the Hart property.