Noah is a young boy fiercely dedicated to finding his missing sister, Megan, even after the rest of the town gives up the search. He is brave and protective but often rushes into situations without thinking or asking for help. His primary motivation is solving the mystery of the Clarksville City Zoo to locate Megan.

Ella is one of the Adventure Scouts and a fiercely loyal friend to Noah. She possesses a bold, curious personality and readily takes action to support her friends. Unlike Noah, she prefers to tackle challenges collaboratively rather than acting alone.

Richie is the quietest and most cautious member of the Adventure Scouts. He relies on his intellect and knowledge, acting as a sensible voice of reason for his more impulsive friends. Despite his natural hesitation and preference for safety, his loyalty keeps him involved in the dangerous investigation.

Megan is Noah's sister and a founding member of the Adventure Scouts who goes missing under mysterious circumstances. Before her disappearance, she explores the local zoo and keeps a detailed journal of the strange things she observes. Her journal pages become the primary clues for her brother's search.

The Shadow Master is a mysterious, antagonistic figure who watches the Adventure Scouts from the darkness. He possesses an unsettling presence and desires to uncover the secrets hidden within the local zoo. His quiet observation creates a constant sense of dread for those investigating the zoo's mysteries.

Charlie Red is a red-haired security guard at the Clarksville City Zoo. He actively patrols the grounds and chases the Adventure Scouts when they ask too many questions or break the rules. He serves as an immediate obstacle to the children's nighttime investigations.

Tank is a senior security guard at the zoo. While he outwardly enforces the rules and kicks the children out of the park, he covertly passes Noah a message to check his mailbox at midnight. He possesses hidden knowledge about the zoo's inner workings.

Mr. Darby is a magical authority figure who seems to be in charge of the hidden areas of the zoo. He acts as a guide who answers the children's questions and explains the zoo's history. He values personal moral responsibility and balances caution with forward progress.

Podgy is a large penguin residing in the Penguin Palace. He acts as a guide to Noah, helping him travel through the aquatic tunnels that lead deep into the hidden areas of the zoo. He is surprisingly determined and loyal.

Blizzard is a polar bear at the Clarksville City Zoo who displays unusual intelligence and behavior. He drops one of Megan's diary pages for the children and later serves as transport across the arctic areas.

Little Big Horn is a rhinoceros living in the zoo. Rather than harming the trespassing children, he gently picks them up and helps move them toward the central areas of the grounds.

Marlo is a bird that evades Noah in his bedroom, dropping a cryptic paper flier onto his bed. The message acts as the inciting clue that directs Noah to the zoo's monkey exhibit.

Mr. Tall Tail is a monkey at the Clarksville City Zoo. He remains still and quiet until Noah is about to leave, at which point he hands the boy a page from Megan's missing diary.

Frederick Jackson is a historical figure whose early childhood trauma and love for exotic animals led to the founding of the zoo. Driven by a desire to keep animals in natural habitats rather than cages, he teamed up with magical individuals to expand the space.

Bhanu Lakshman is a man from India who possessed magical abilities. He agreed to help Frederick Jackson expand the zoo using magic, provided it could be used as a sanctuary for a secret organization dedicated to protecting endangered animals.