Michael is a ten-year-old boy attending a boarding school in Wiltshire, England, where he feels deeply miserable. Punished by his teachers and targeted by classmates, he seeks an escape from his daily torment by running away. His rainy flight leads him to a sprawling, ivy-covered estate, where a chance encounter with an older woman introduces him to a remarkable story about Africa and a white lion.

Bertie is an adventurous but deeply lonely boy raised behind the high fences of his family's South African cattle compound. Eager to explore the veldt and observe the local wildlife, he feels stifled by his father's strict rules. His life changes forever when he disobeys orders to rescue an orphaned animal, establishing a profound connection that shapes his entire future.

Introduced as an elderly woman living in a vine-covered estate in Wiltshire, Millie serves as the primary storyteller for the runaway Michael. Through her memories, she reveals her past as an isolated girl growing up in a massive house with strictly enforced rules. She eventually forms a powerful bond with a boy who escapes his nearby boarding school, setting the course for her steadfast devotion.

An orphaned white lion cub rescued from predators in the South African veldt. Hand-raised in a farmhouse compound, he loses his ability to survive in the wild but gains an unbreakable bond with his human companions. He grows into a majestic creature whose unique coloring eventually draws the attention of a traveling circus owner.

Bertie's mother is an English woman struggling to adapt to life on a secluded cattle farm in the Timbavati region. She suffers from frequent bouts of malaria and chronic sadness, feeling entirely isolated by her harsh surroundings. When her son brings home a wild cub in need of rescue, she displays a sudden maternal ferocity that temporarily revitalizes her spirit.

A stern cattle rancher, Bertie's father attempts to impose strict order on his farm and his family. He builds a high fence around the compound to keep the dangers of the veldt at bay, inadvertently isolating his wife and son from the outside world. He values practical farm management over emotional warmth or familial connection.

Millie's father is a largely absent figure who delegates the raising of his daughter to hired staff following the death of his wife. He spends most of his time working in London, resulting in a disconnected relationship with Millie. When conflict breaks out, he immediately enlists in the military.

Nanny Mason serves as the warm, maternal presence in young Millie's otherwise cold upbringing. Following the loss of Millie's mother, she provides the comfort and steady guidance the young girl desperately needs. She remains a permanent, supportive fixture as Millie grows older.

Miss Tulips is a live-in governess hired to educate young Millie. Strict and severe, she moves through the house like a cold shadow. Her thin-lipped, unsmiling expression earns her the secret nickname "Nolips" from her lonely student.

A kindly French circus owner who travels to Africa to acquire animals for his European show, Le Cirque Merlot. He purchases the rare white lion cub to exhibit him as a star attraction. Despite removing the animal from its home, Merlot genuinely cares for his creatures.

Jack is a large dog belonging to the older Millie Andrews. He acts as her loyal companion and protector on the estate, though he quickly settles down to rest by the kitchen fire once visitors are welcomed inside.

Basher Beaumont is a bully at the Wiltshire boarding school attended by young Michael Morpurgo. His cruel behavior contributes significantly to Michael's profound misery and ultimate decision to flee the institution.

Mr. Carter is a harsh teacher at the boarding school who torments young Michael Morpurgo over his poor spelling. His punishing methods make the educational environment unbearable for struggling students.

Mr. Cook is a history teacher at the Wiltshire boarding school. He possesses knowledge about the school's past alumni and directs curious students toward the chapel's memorial plaques to learn about former attendees.