Jaxon is an observant nine-year-old boy living in contemporary Brooklyn. He usually follows the rules and tries to hide his anxieties so he does not worry his mother. His curiosity and desire to help pull him into an unexpected interdimensional mission to transport three baby dragons.

Ma is an elderly witch living in Brooklyn who serves as a guardian of supernatural secrets. She wears a purple housecoat and uses a wooden cane, with white hair that resembles an angry cloud. Though gruff and exhausted by her long career without an apprentice, she possesses deep knowledge of other dimensions and magical creatures.

Alicia is Jaxon's devoted single mother who fights fiercely to keep a roof over her son's head. She shares Jaxon's dark eyes and curly eyebrows, frequently showering him with affection. The stress of impending homelessness and a complicated past with magic make her intensely protective of her ordinary life.

Kavita is Vikram's younger sister. She is inquisitive and impulsive, often letting her curiosity override rules or boundaries. Her well-intentioned but misguided attempt to comfort a hungry creature drastically alters the course of Jaxon's mission.

Charlie, who goes by Trouble, is an interdimensional navigator and magical practitioner. He dresses warmly and carries an air of regret regarding his past family mistakes. Finding purpose in the magical community, he uses his supernatural skills to help others and hopes to eventually repair the rift with his daughter.

Vikram is Jaxon's best friend and a reliable source of information. His parents view Jaxon as a good influence on him. Vikram possesses an extensive knowledge of dinosaurs, making him the perfect person to call when Jaxon needs to identify prehistoric eras.

Ambrose is an unhoused man who acts as a trusted keeper of Brooklyn's supernatural secrets. He wears thick layers of clothing because he is completely invisible to the human eye. He guards the disused park structures that secretly function as magical transporters.

Sis is a stern, serious woman who resides in the other dimension. She firmly believes that all magical creatures belong strictly in their own world and distrusts humans who interfere with them. She holds high standards for accountability and expects Ma to uphold her promises.

L. Roy Jenkins is a professor and a member of the magical community who previously lived in Madagascar. He holds the progressive view that Earth and the magical dimensions should merge, believing that magic will inevitably find its way back into the human world.

Nate is a massive, talking rat who accompanies Charlie. Unlike ordinary Brooklyn rodents, Nate is friendly and highly intelligent. He possesses the unique ability to smell both magical energy and human emotions like regret.